I WILL BRAINLIST ITS ONLY ONE PROBLEM !!!!!!!!!!!!!!!

I WILL BRAINLIST ITS ONLY ONE PROBLEM !!!!!!!!!!!!!!!

Answers

Answer 1

Answer:

11/200

Step-by-step explanation:

This is the correct answer boo

Answer 2
11/200 is the answer lol

Related Questions

Yoko made $306 for 18 hours of work.
At the same rate, how much would she make for 8 hours of work?
What’s the answer I need help

Answers

Answer:

$136.

Step-by-step explanation:

Divide how much they made by the # of hours. 306/18=17. Multiply the amount per hour 17 by the 8 hours of work. 17x8=136.

in 2015, the number of fish in a pond was 80. In 2016 The number of fish declined by 75% How many fish were in the pond in 2016?​

Answers

I think the the answer is 20

What is the value of p?



p+2−4=14



Drag and drop the correct answer in the box.

p = Response area

Answers

Hi :)

p= 16

Subtract 4 from 2 to get −2
p−2=14

Add 2 to both sides
p=14+2


Add 14 and 2 to get 16
p= 16


Hope this helps :)

Answer: p=16

Step-by-step explanation:

If Jan is 3 years older now than Dale was 2 years ago, then Jan is how many older than Dale is right now.
A) 1 year
B) 2 years
C) 3 years
D) 5 years​

Answers

the answer is a (1 year)

Which expression is equivalent to |-5| + |-3|

Answers

Answer:

5+3

Step-by-step explanation:

5+3

Answer:

5+3=8

Step-by-step explanation:

Please answer this correctly without making mistakes

Answers

Answer: 96%

1 square represent 1%

Answer:

96 present

Step-by-step explanation:

NEED A MATH TUTOR ASAP !!!

tim has $20 in a savings account. The interest rate is 10% per year and is not compounded. How much will he have in 1 year ?

Answers

Answer:

$22

Step-by-step explanation:

20 * 1.10 = 22

The answer is $22 good luck!!

a block is 12 g and volume is 6 what is the density

Answers

Answer: c.)2 g/ml is the correct answer.

8. Fay Teng's expenditures for the past 3 months were: August,
$1,735.50; September, $1,829.42; and October, $1,793.88.
What is her average monthly expenditure?
9. You use the utility company's budget plan for paying your
home heating bills. You pay $75 a month for 9 months. Your
actual bills are: September, $28.95; October, $16.15; November,
$68.46; December, $109.34; January, $115.26; February. $94.19;
March $75.66; April, $51.97; and May, $49.16. Compute the
average for the 9 months.
ght The McGraw-e Companies, Inc. All rights

Answers

=$75.66 all in all and $67.99 dollars

Name the slope and one point that is on the line
represented by the equation: y-6 = 9(x - 1)
A) m = -9 and point (-1,-6)
B) m = 9 and point (-1,-6)
C) m = 9 and point (1,6)
D) m = -9 and point (1,6)

Answers

Answer:

B

Step-by-step explanation:

the correct answer is b

Determine if the sequence below is arithmetic or geometric and determine the common difference/ratio in simplest form
12,6,3

Answers

Answer:

The sequence is geometric

The common ratio is 0.5

Step-by-step explanation:

In the arithmetic sequence, there is a common difference between each two consecutive terms

In the geometric sequence, there is a common ratio between each two consecutive terms

Let us check the given sequence

∵ The first 3 terms are 12, 6, 3

∵ 6 - 12 = -6

∵ 3 - 6 = -3

∵ There is no common difference between the consecutive terms

The sequence is not an arithmetic sequence

∵ 6 ÷ 12 = 0.5

∵ 3 ÷ 6 = 0.5

∴ There is a common ratio between each two consecutive terms

The sequence is a geometric sequence

The common ratio is 0.5

Given sequence is geometric sequence and common ratio between consecutive term is  [tex]\frac{1}{2}[/tex] .

In Arithmetic sequence , common difference between consecutive terms should be equal.

In Geometric sequence, common ratio between consecutive terms should be equal.

Given sequence,     12, 6, 3, ...

  Since, common difference =  [tex]6-12\neq 3-6[/tex] , this is not arithmetic sequence.

Common ratio =     [tex]\frac{6}{12}=\frac{3}{6}=\frac{1}{2}[/tex]  Because common ratio is are equal. Thus, given sequence is geometric sequence.

Learn more about sequence here :

https://brainly.com/question/17648677

what number is 1/10 of 8000000

Answers

Answer:

800000

Step-by-step explanation:

The standard height from the floor to the bull’s-eye at which a standard dartboard is hung at 5 feet 8 inches. A standard dartboard is 18 inches in diameter. Suppose a standard dartboard is hung at standard height so that the bull’s-eye is 10 feet from the wall to its left. Sasha throws a dart at the dartboard that land at point 10.25 Feet from the left wall and 5 feet above the floor. Does Sasha’s dart land on the dartboard? Drag the choices into the boxes to correctly complete the statements.

Answers

Answer:

Hello! I'm sorry I couldn't get to your question sooner. I just completed this quiz!

The equation of the circle that represents the dartboard is (x-10)^2 + (y-17/3)^2 = 9/16, where the origin is the lower-left corner of the room and the unit of the radius is feet.  

The position of Sasha's dart is represented by the coordinates (10.25,5). Sash's dart does land on the dartboard.

This quiz was completed on k12, lesson 3.03.

The question is an illustration of equation of circles.

The equation of the dartboard circle is: [tex]\mathbf{(x - 10)^2 + (y - \frac{17}3)^2 = \frac 9{16}}[/tex]Sasha's dart lands on the dartboard because

From the question, we understand that:

[tex]\mathbf{h = 5\ ft\ 8\ in }[/tex] ---- the height at which the dartboard was hung

[tex]\mathbf{d = 18\i n }[/tex] ---- the diameter of the dartboard

[tex]\mathbf{B = 10ft}[/tex]  --- the bull's eye

[tex]\mathbf{D = (10.25ft, 5ft)}[/tex] --- Sasha's dart

Equation of the circle

First, we convert all units to feet

This is done by dividing inches units by 12

[tex]\mathbf{h = 5\ ft\ 8\ in }[/tex]

[tex]\mathbf{h = 5\ ft\ + \frac{8}{12}\ ft }[/tex]

[tex]\mathbf{h = 5\ ft\ + \frac{2}{3}\ ft }[/tex]

Take LCM

[tex]\mathbf{h = \frac{15 + 2}{3}\ ft }[/tex]

[tex]\mathbf{h = \frac{17}{3}\ ft }[/tex]

[tex]\mathbf{d = 18\i n }[/tex]

[tex]\mathbf{d = \frac{18}{12}ft}[/tex]

[tex]\mathbf{d = \frac{3}{2}ft}[/tex]

Divide by 2 to calculate radius

[tex]\mathbf{r = \frac{3}{2*2}ft}[/tex]

[tex]\mathbf{r = \frac{3}{4}ft}[/tex]

The equation of the circle is represented as:

[tex]\mathbf{(x - a)^2 + (y - b)^2 = r^2}[/tex]

In this case:

[tex]\mathbf{a = B = 10ft}[/tex] -- the distance between the bull's eye and the wall

[tex]\mathbf{b = h = \frac{17}{3}\ ft }[/tex] ---- the height at which the dartboard was hung

So, we have:

[tex]\mathbf{(x - a)^2 + (y - b)^2 = r^2}[/tex]

[tex]\mathbf{(x - 10)^2 + (y - \frac{17}3)^2 = (\frac 34)^2}[/tex]

Evaluate the exponents

[tex]\mathbf{(x - 10)^2 + (y - \frac{17}3)^2 = \frac 9{16}}[/tex]

Hence, the equation of the circle is: [tex]\mathbf{(x - 10)^2 + (y - \frac{17}3)^2 = \frac 9{16}}[/tex]

Does Sasha’s dart land on the dartboard?

Yes her dart lands on the dartboard because

[tex]\mathbf{D = (10.25ft, 5ft)}[/tex] is within the circumference of the dartboard

Read more about equation of circles at:

https://brainly.com/question/23988015

SHOW YOUR WORK! PLEASE HELP ASAP.
ITS REALLY SIMPLE PLEASE HELP DONT IGNORE

Xavier is solving a problem on the whiteboard as shown.
Part A. Is Xavier's solution correct? If not, identify where he made an error.
Part B. Solve 7950 divided by 25.

Answers

Let us see how we can solve this step by step each :

6417 ÷ 31 , we divide 64 by 31 and get the resulting quotient as 2 .

Then we bring down 1 . So , the number below is 21 , which cannot be divided by 31 .

So , we will have to bring down 7 for which we have to add a 0 to the quotient . Then the quotient will become 20 as of now .

As 217 is divisible by 3 , I put seven near 21 , making the quotient as 217 and get the remainder 0 .

Hence in the correct solution the correct quotient = 207 .

In Xavier's solution :

But the same thing has not been done in Xavier's solution as he has put a 0 after 7 instead of putting it before 7 . Hence , Xavier's mistake is that he put the 0 after 7 instead of putting it before 7 .

In Xavier's solution the quotient is = 270

Therefore , Xavier's mistake is that he put the 0 after 7 instead of putting it before 7 .

For each of the following cases [(a), (b), and (c)], (I) state whether the study should be observational or experimental. (II) state whether the study should be run blind, doubleblind, or neither. If the study should be run blind or double-blind, who should be blinded?(a) An investigation of whether taking aspirin reduces one’s chance of having a heart attack.(b) An investigation of whether babies born into poor families (family income below $25,000) are more likely to weigh less than 5.5 pounds at birth than babies born into wealthy families (family income above $65,000).(c) An investigation of whether the size of the midsagittal plane of the anterior commisssure (a part of the brain) of a man is related to the sexual orientation of the man.

Answers

Answer:

(a) An investigation of whether taking aspirin reduces one’s chance of having a heart attack.

Experimental

Neither blind nor double-blind (unless a placebo is being administered to some participants).

(b) An investigation of whether babies born into poor families (family income below $25,000) are more likely to weigh less than 5.5 pounds at birth than babies born into wealthy families (family income above $65,000).

Observational

There is no blinding issue here.

(c) An investigation of whether the size of the midsagittal plane of the anterior commissure (a part of the brain) of a man is related to the sexual orientation of the man.

Observational

There is no blinding issue here.

Step-by-step explanation:

An observational study happens where some variables are observed to determine their correlations.   On the other hand, in experimental studies, the researcher controls certain variables to determine causality.  Therefore, an experimental study provides evidence of cause and effect, like in (a) above.

A line has a slope of 9 what is the slope of a line it is perpendicular to this line? *

9
-9
1/9
-1/9

Answers

Answer: -1/9

Explanation: Perpendicular lines have negative reciprocal slopes.

A negative reciprocal slope is a fancy way of

saying flip the fraction and change the sign.

Notice that our slope is an integer.

We can turn it into a fraction by putting it over 1.

So we have 9/1.

A line perpendicular to this would be a negative reciprocal.

So flip the fraction, giving us 1/9, and change the sign to get -1/9.

An environmental engineer is tasked with determining whether a power plant cooling system is heating the water it uses more than allowed by environmental regulations. They measure water temperatures at the cooling system input and the cooling system output for several different days in several different seasons.A data file containing these measurements is HW_PTA 243.csv.Do a statistical analysis on this data to determine if the temperature change between the input and output of the cooling system is different than 6 degrees. What does your analysis indicate?
A) The cooling system changes the temperature of the water by an amount different than 6 degrees.
B) The cooling system changes the temperature of the water by 6 degrees.

Answers

Complete Question

The complete question is shown on the first , second and third uploaded image

Answer:

A

 The correct option is A

B

  The correct option is H

Step-by-step explanation:

The null hypothesis is  [tex]H_o  :  \mu_1 - \mu_2 =  6[/tex]

The alternative  hypothesis is  [tex]H_a  :  \mu_1 - \mu_2 \ne  6[/tex]      

The population mean difference is  [tex]\mu_d  =  6[/tex]

Generally the sample size is  n =  15      

Generally the sample mean for input temperature is mathematically represented as

      [tex]\= x _1  = \frac{\sum x_i }{n}[/tex]

=>    [tex]\= x _1  = \frac{57.6 + 68.9 + \cdots +60.4  }{15}[/tex]  

=>    [tex]\= x _1  = 62.57 [/tex]  

Generally the sample mean for output temperature is mathematically represented as

      [tex]\= x _2  = \frac{\sum x_i }{n}[/tex]

=>    [tex]\= x _2  = \frac{65.1+ 74.4 + \cdots +67.3 }{15}[/tex]  

=>    [tex]\= x _2  = 55.97 [/tex]  

Generally the sample mean difference is mathematically represented as

   [tex]\= d = 62.57 - 55.97[/tex]

=>[tex]d = 6.6[/tex]

Generally the standard deviation is mathematically represented as

       [tex]s_d  =  \sqrt{\frac{ \sum [d_1 - \= d]^2}{n-1} }[/tex]

=>    [tex]s_d  =  \sqrt{\frac{ [ [57.6 -65.1]- 6.6]^2 +[68.9 -74.4]- 6.6]^2+\cdots +   [60.4 -67.3]- 6.6]^2}{15-1} }[/tex]

=>     [tex]s_d  = 1.732 [/tex]

Generally the test statistics is mathematically represented as

      [tex]t =  \frac{6.6  - 6 }{\frac{1.732}{\sqrt{15} } }[/tex]

=>   [tex]t = 1.342 [/tex]

Generally the degree of freedom is mathematically represented as

    [tex]df  = n -  1[/tex]

So

      [tex]df  =  15  -  2[/tex]

=>    [tex]df  =  14[/tex]

Generally the p-value  is mathematically represented as

     [tex]p-value  = 2 *  P(t >  1.342 )[/tex]

Generally from the t -distribution table the probability of 1.342 at a degree of freedom of  [tex]df  =  28[/tex] is  

       [tex]P(t >  1.342 ) = 0.10047[/tex]

So

     [tex]p-value  = 2 * 0.10047[/tex]

=>   [tex]p-value  = 0.201[/tex]

Generally from the value  obtained we see that [tex]p-value  > \alpha[/tex] Hence

The  decision rule is  

Fail to  reject the null hypothesis

The conclusion is

The cooling system changes the temperature of the water by 6 degrees

Research shows that many banks are unwittingly training their online customers to take risks with their passwords and other sensitive account information, leaving them more vulnerable to fraud (Yahoo, July 23, 2008). Even web-savvy surfers could find themselves the victims of identity theft because they have been conditioned to ignore potential signs about whether the banking site they are visiting is real or a bogus site served up by hackers. Researchers at the University of Michigan found design flaws in 78% of the 214 U.S. financial institution websites they studied.

Required:
Is the sample evidence sufficient to conclude that more than three out of four financial institutions that offer online banking facilities are prone to fraud? Use a 5% significance level for the test.

Answers

Answer:

Decision rule

Fail to reject the null  hypothesis

Conclusion

The sample evidence is not sufficient to conclude that more than three out of four financial institutions that offer online banking facilities are prone to fraud.

Step-by-step explanation:

From the question we are told that

  The sample size is  n =  214

   The sample proportion is p = 0.78

   The level of significance is [tex]\alpha = 0.05[/tex]

Generally the population proportion is mathematically represented as

      [tex]p = \frac{3}{4} =0.75[/tex] (gotten from the statement  ''three out of four'' in the question)

The null hypothesis is [tex]H_o : p = 0.75[/tex]

The alternative hypothesis [tex]H_a : p > 0.75[/tex]

Generally the test statistics is mathematically represented as

     [tex]z = \frac{\^{p} - p}{ \sqrt{\frac{p(1-p)}{n} } }[/tex]

=>    [tex]z = \frac{0.78- 0.75}{ \sqrt{\frac{ 0.75(1-0.75)}{214} } }[/tex]

=>  [tex]z = 1.01[/tex]

Generally the p-value is mathematically represented as

    [tex]p-value  = P(Z > z )[/tex]

=> [tex]p-value  = P(Z > 1.01 )[/tex]

From the z-table  

    [tex]P(Z > 1.01 ) = 0.15625[/tex]

So

    [tex]p-value  = 0.15625 [/tex]

From the obtained values we see that [tex]p-value > \alpha[/tex] hence we fail to reject the null hypothesis

 Therefore we can conclude that the sample evidence is  not  sufficient to conclude that more than three out of four financial institutions that offer online banking facilities are prone to fraud.

Given g(x) = –2x – 1, find g(1).

Answers

Answer:

-3

Step-by-step explanation:

g(1)=-2-1

g(1)=-3

Brainliest appreciated!

Use long division to find the quotient below.
(16x3 + 40x2 + 72) - (2x+6)
A. 8x2 + 3x + 12
O B. 8x2 - 4x + 12
C. 8x2 + 5x + 12
D. 8x2 - 6x + 12

Answers

Long polynomial division ~
Answer-
B. 8x2-4x+12

Points that do not lie in the same plane are called________points​

Answers

Answer:

non - collinear points

Step-by-step explanation:

points that dont lie on the same line

Water flows back and forth between a small and large tank. When water is moving into a tank the flow rate is

positive, and when water is moving from a tank the flow rate is negative. The large tank begins with 300 gallons of

water, and the small tank begins with 200 gallons of water. After a period of 5 minutes, the large tank has the same

amount of water as the small tank. Which statement describes the flow rate?

The flow rate of the large tank is 10 gal/min, and the flow rate of the small tank is -10 gal/min.

O The flow rate of the large tank is -10 gal/min, and the flow rate of the small tank is 10 gal/min.

The flow rate of the large tank is 20 gal/min, and the flow rate of the small tank is -20 gal/min.

The flow rate of the large tank is -20 gal/min, and the flow rate of the small tank is 20 gal/min.

Save and Exit

Answers

Answer:

D. The flow rate of the large tank is -20 gal/min, and the flow rate of the small tank is 20 gal/min.

Step-by-step explanation:

Flow rate = [tex]\frac{gallons of water}{minute}[/tex]

flow rate of water in the big tank = [tex]\frac{300}{5}[/tex]

                         = 60 gallons/minute

flow rate in the smaller tank = [tex]\frac{200}{5}[/tex]

                          = 40 gallons/minute

The difference in flow rate between the tanks = 60 - 40

                          = 20 gallons/minute

Since the two tanks have the same amount of water after the given time, then the volume of water in the large tank decrease; while the volume of water in the small tank increased.

Therefore, the flow rate of the large tank is -20 gal/min, and the flow rate of the small tank is 20 gal/min. This shows that option D is correct.

Answer:

B

Step-by-step explanation:

took the quiz

Write down the gradient of the line y =-4r+7.​

Answers

4
x
+
y
=
7
or
y
=

4
x
+
7
Comparing withe general equation of a straight line
y
=
m
x
+
c
we get slope
m
=

4
.
Putting x=0 in the equation we get
y
=
7
. So y-intercept is
y
=
7
graph{4x+y=7 [-20, 20, -10, 10]} [Ans]

Can someone please help me with this question (there are more questions like this that I will post later, if your answer is correct I will give you brainliest)

Answers

Answer:

1. alterative exterior angles.

Step-by-step explanation:

I don't know what the rest of the other options are. So I can't answer the rest.

9=2m+2-3
please tell me what dis is​

Answers

Answer:

m=5

Step-by-step explanation:

Answer:

5

Step-by-step explanation:

Step 1:

9 = 2m + 2 - 3        Equation

Step 2:

9 = 2m - 1        Combine Like Terms

Step 3:

10 = 2m       Add 1 on both sides

Step 4:

m = 10 ÷ 2       Divide

Answer:

m = 5

Hope This Helps :)

A thermometer shows a temperature of Negative 20 and three-fourths degrees. A chemist recorded this temperature in her notebook using a decimal. Which number did the chemist write in the notebook?
Negative 21.ModifyingAbove 4 with bar
Negative 21.ModifyingAbove 3 with bar
Negative 20.75
Negative 20.34

Answers

Answer:

The answer is C.

Step-by-step explanation:

3/4 is equal to 0.75. If you combine 0.75 with -20, then it is 20.75.

Answer:

C

Step-by-step explanation:

9. Determine whether KM and ST are parallel, perpendicular, or neither. K(-1, -8), M(1,6), S(-2,-6), T(2, 10) A Parallel B Perpendicular C Neither​ Hint(use slope formula)

Answers

Neither: the slope for KM=7, and the slope for ST= 1

A circle has a diameter of 60m. What is its circumference?

Answers

The circumference would be 188.5m

Factorise fully
-y - 6


this is my last question for today, right answer will be marked brainiest​

Answers

Answer:

[tex]-(y+6)[/tex]

Step-by-step explanation:

[tex]-y-6\\\\=-(y+6)[/tex]

Answer:

-(y+6)

Step-by-step explanation:

[tex] - y - 6[/tex]

Common factor : -1

[tex] - 1(y + 6) = \\ - (y + 6)[/tex]

After the first week of registration, 92 children had enrolled for the second
session of summer camp. If this represents 80% of the available slots, what
is the maximum number of children the camp can enroll for the second
session?

Answers

Answer:

115 children

Step-by-step explanation:

Please see the attached picture for the full solution.

Other Questions
A force of 49N causes a box to move with an acceleration of 7m/s2. Find the mass of the object +5y = 33 - 2y = -8 A 34-year-old woman has a maximum heart rate of 175 bpm. She plans an exercise program so that her heart rate will be between 80% and 90% of her maximum heart rate for at least 30 minutes a day, 3 days a week. Calculate the desired range of heart beats per minute for this exercise program why did the british need to tax more PLEASE HELP ANY ENGLISH MASTER!!Paraphrasing means rewriting a sources ideas in your own words and word order AND A.) citing the source in the signal phrase or in ( ).B.) using quotation marks.C.) using a thesaurus to change a few words Click to review the online content. Then answer the question (s) below, using complete sentences. Scroll down to view additional questions. Online Content Site 1 Explain how trees can fall up. How does this situation help the local economy? ( Site 1) That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.According to the passage, where does government get its power?from Godfrom the peoplefrom the Declaration of Independencefrom other forms of government Can someone help me with this I really need help Which four capitals are located between 60W and 70W longitude? What did the Vikings do that made people consider them as a large threat which of the equation is graphed belowA.) y=1/4x+1B.) y=-1/4x+1C.) y=4x+1D.) y=-4x+1 Lisez la rponse suivante. Quelle question a-t-on pose ? Choisissez toutes les questions possibles.- ____________________ ?- Je n'ai rien fait !Qu'est-ce que vous avez fait ?Qu'avez-vous fait ?Qui avez-vous vu ?Avez-vous fait quelque chose d'illgal ?Avec qui tes-vous venu au muse ? On January 1, Merry Walker established a catering service. Listed below are accounts to use for transactions (a) through (f), each identified by a number. Following are the transactions that occurred in Walker's first month of operations. You need to indicate for each transaction the accounts that should be debited and credited by selecting the account number(s). 1. Cash 2. Accounts Receivable 3. Supplies 4. Prepaid Insurance 5. Equipment 6. Truck 7. Notes Payable 8. Accounts Payable 9. Merry Walker, Capital 10. Merry Walker, Drawing 11. Fees Earned 12. Wages Expense 13. Rent Expense 14. Utilities Expense 15. Truck Expense 16. Miscellaneous Expense 17. Insurance Expense What is the range of a set of data. A. The middle number. B. The average of the data. C. The difference in the largest value from the smallest value. D. The largest value of the data What is the solution of 8 + a = 13? Justify each step. A. The steps are: (1) 8 + a = 13 (2) 8 + 8 + a = 13 + 8 (3) a = 21 The reasons are: (1) original equation (2) Addition Property of Equality (3) Simplify. B. The steps are: (1) 8 + a = 13 (2) 8 8 + a = 13 (3) a = 13 The reasons are: (1) original equation (2) Subtraction Property of Equality (3) Simplify. C. The steps are: (1) 8 + a = 13 (2) 8 8 + a = 13 8 (3) a = 5 The reasons are: (1) original equation (2) Subtraction Property of Equality (3) Simplify. D. The steps are: (1) 8 + a = 13 (2) 88+a=138 (3) a = 1.63 The reasons are: (1) original equation (2) Division Property of Equality (3) Simplify. misty is driving on a scenic road trip, and the graph shows the number of hours traveled compared to the number of miles of the trip remaining. Use the graph below to the answer.Write an equation of the graph in slope-intercept form.A. y=-100/3x+450B. y=100/3x-450C. y=450x+100/3 The tune of the song is referred to as the melody.TrueFalse Refer to your periodic table:Which of the following has the smallest atomic radius?BromineAstatineIodineFluorine Warm up is another name for stretching True or false Many workplace safety rules are created by which government agency?