need answer thanks! only answer if you know please!
Answer:
a) [tex]k \approx 0.0602\,\frac{1}{min}[/tex] ([tex]k\approx 6.02\,\frac{\%}{min}[/tex]), b) [tex]k \approx 0.0648\,\frac{1}{min}[/tex] ([tex]k \approx 6.48\,\frac{\%}{min}[/tex]), c) [tex]t_{1/2} \approx 60.274\,days[/tex], d) [tex]t_{1/2}\approx 4.305\,min[/tex], e) [tex]k \approx 0.3\,\frac{1}{min}[/tex] ([tex]k\approx 30\,\frac{\%}{min}[/tex]), f) [tex]k \approx 0.0120\,\frac{1}{min}[/tex] ([tex]k \approx 1.20\,\frac{\%}{min}[/tex]), g) [tex]k \approx 2.876\times 10^{-5}\,\frac{1}{yr}[/tex] ([tex]k \approx 2.876\times 10^{-3}\,\frac{\%}{yr}[/tex])
Step-by-step explanation:
All radioactive isotopes decay exponentially, the mass of the isotope as a function of time ([tex]m(t)[/tex]), measured in grams, is defined by:
[tex]m(t) = m_{o}\cdot e^{-k\cdot t}[/tex] (1)
Where:
[tex]m_{o}[/tex] - Initial mass of the isotope, measured in grams.
[tex]k[/tex] - Decay rate, measured in [tex]\frac{1}{min}[/tex] or [tex]\frac{1}{day}[/tex] or [tex]\frac{1}{yr}[/tex].
[tex]t[/tex] - Time, measured in minutes, days or years.
We define the decay rate in terms of half-life by using the following expression:
[tex]k = \frac{\ln 2}{t_{1/2}}[/tex] (2)
Where [tex]t_{1/2}[/tex] is the half-life of the isotope, measured in minutes or years.
Now we proceed to determine the missing values:
a) Polonium-200 ([tex]t_{1/2} = 11.5\,min[/tex])
[tex]k = \frac{\ln 2}{11.5\,min}[/tex]
[tex]k \approx 0.0602\,\frac{1}{min}[/tex]
b) Lead-194 ([tex]t_{1/2} = 10.7\,min[/tex])
[tex]k = \frac{\ln 2}{10.7\,min}[/tex]
[tex]k \approx 0.0648\,\frac{1}{min}[/tex]
c) Iodine-125 ([tex]k = 0.0115\,\frac{1}{day}[/tex])
[tex]t_{1/2} = \frac{\ln 2}{k}[/tex]
[tex]t_{1/2} = \frac{\ln 2}{0.0115\,\frac{1}{day} }[/tex]
[tex]t_{1/2} \approx 60.274\,days[/tex]
d) Kryption-75 ([tex]k = 0.161\,\frac{1}{min}[/tex])
[tex]t_{1/2} = \frac{\ln 2}{k}[/tex]
[tex]t_{1/2} = \frac{\ln 2}{0.161\,\frac{1}{min} }[/tex]
[tex]t_{1/2}\approx 4.305\,min[/tex]
e) Strontium-79 ([tex]t_{1/2} = 2.3\,min[/tex])
[tex]k = \frac{\ln 2}{2.3\,min}[/tex]
[tex]k \approx 0.3\,\frac{1}{min}[/tex]
f) Uranium-229 ([tex]t_{1/2} = 58\,min[/tex])
[tex]k = \frac{\ln 2}{58\,min}[/tex]
[tex]k \approx 0.0120\,\frac{1}{min}[/tex]
g) Plutonium-239 ([tex]t_{1/2} = 24100\,yr[/tex])
[tex]k = \frac{\ln 2}{24100\,yr}[/tex]
[tex]k \approx 2.876\times 10^{-5}\,\frac{1}{yr}[/tex]
26 _Is this number rational or irrational? 0.5287593593593593 Explain why?
Answer:
Irrational means it can not be written completely. If there was a line above the last number/the number was infinite, it would be irrational. But because it stops, its not irrational. It can be written as a fraction, so it is rational.
Which expression is equivalent to 42 + 12? 7(6+5) 2(40+6) 6(7+2) 10(32+2)
Answer:
6(7+)
Step-by-step explanation:
1) Start by solving the original equation
42 + 12 = 54
2) Solve the other equations until you find a match
2a) Start with what's in the parenthesis
7(6+5) = 7(11) = 77
2b)
2(40+6) = 2(46) = 92
2c)
6(7+2) = 6(9) = 54
This is your answer
2d)
10(32+2) = 10(34) = 340
Answer: 6(7 +2)
Step-by-step explanation:
Calculate 42 + 12, which is 54.
Calculate 7(6 + 5), which is 7 * 11 = 77.
Calculate 2(40 + 6), which is 2 * 46 = 92.
Calculate 6(7 + 2), which is 6 * 9 = 54.
Calculate 10(32 + 2), which is 10 * 34 = 340.
And, we can conclude the expression 6(7 + 2) is equivalent to 42 + 12.
Using 3.14 for π, calculate the circumference and area of the circle below. Include your answer to the hundredths place.
Circumference:
feet and the area ft squared:
If you don't know the answer please don't respond need ASAP
Answer:
37.68
Step-by-step explanation:
GIVING BRAINLIEST PLEASE HELPPPPPPPPPPPPP
Answer:
C
Step-by-step explanation:
The number of tips that the server gets is dependent on how many customers she serves.
Hope this helps!
Answer:
i dont understand
Step-by-step explanation:
but probably c
Triangles 1 and 2 have the angle measures as shown.
Which statement is correct about triangle 1 and triangle 2?
PLEASE HELP
Answer:
The second one or the last one, but those two are the ones i came up with
Step-by-step explanation:
Christina has 50 coins consisting of quarters and dimes. The coins combined value is $9.50. Write a system of equation to determine how many quarters and dimes Christina has.
Answer:
Christina has 30 quarters and 20 dimes.
Step-by-step explanation:
Given that a quarter is worth 0.25 dollars and a dime is worth 0.10 dollars, if Christina has 50 coins and these add up to a total of $ 9.50, to determine the number of quarters and dimes that she has in her possession, the following calculation must be carried out, taking into account that the difference between a quarter and a dime is 0.15 dollars:
50 x 0.25 = 12.5
12.5 - 9.5 = 3
Thus, the difference between the value that Christina has and the value that she would have if all of her coins were quarters is 3 dollars. Thus, since 0.15 x 20 equals 3, of the 50 coins Christina has, 30 are quarters and 20 are dimes.
This is confirmed through the following equation:
30 x 0.25 + 20 x 0.1 = X
7.5 + 2 = X
9.5 = X
Monthly income of A and B are in the ratio 5:6. If A earns $3,300 less than B, then what is their total income?
Answer:
a+3300=b
5a+3300=6a
minus 5a both sides
a=3300
3300*5=16500
3300*6=19800
16500+19800=36300
$36,300
I need help for this question.
Answer:
the water rises 50ft per minute so for 60min you have to multiply 60 x 50 which will be 3000ft in 60mins
Step-by-step explanation:
I WILL GIVE BRAINLIEST!!!
Step-by-step explanation:
What is 0.031+10+2.2
Answer:
12.231
Step-by-step explanation:
you add them with the zeros
Answer:
12.231
Step-by-step explanation:
0.031+10+2.2
10.031+2.2
12.231
On Sunday, a local hamburger shop sold a combined total of 448 hamburgers and cheeseburgers. The number of cheeseburgers sold was three times the
number of hamburgers sold. How many hamburgers were sold on Sunday?
Answer:
How many hamburgers were sold on Sunday?
336
In kite ABCD, BE = –x + 6 and ED = 0.5x. Determine the value of x in the kite shown. Question 2 options: A) x = –12 B) x = –3 C) x = 4 D) x = 9
Answer:
4
Step-by-step explanation:
–x + 6 = 0.5x
–(4) + 6 =.5(4)=2
-x-.5x=-6
-1.5x=-6
X=4
Answer:
x=4
Step-by-step explanation:I took the test
Solve:
7 (x -3)
What is the answer
Answer:
7x-21
Step-by-step explanation:
Which point represents the opposite of -2? 1 + 1 35 33 2 В
What is an equation of the line that passes through the point (−5,2) and is parallel to the line 4x-5y=5
PLSSSSSS I NEED HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Simplify Expressions:
[tex]\sqrt{(3-\sqrt{19} )^{2} }[/tex]
Answer:
1.358899 or 3-\sqrt{19}
Step-by-step explanation:
either or
How many solutions does this system of equations have?
Answer:
I believe the answer is '2 solutions'.
Step-by-step explanation:
Combine each equation, solve the resulting question which comes out as two seperate variables, x = -1.197-- and y = 7.3990. I believe your answer is '2 solutions' because of this.
Answer:
1 solution
Step-by-step explanation:
For the class field trip, the fourth grades at Jefferson Elementary School need to take buses. Each bus fits 55 students and there are 200 students in fourth grade. How many buses will they need?
3 buses
3 R20 buses
4 buses
None of these is correct.
They will need 4 buses.
What is division?The division in mathematics is one kind of operation. In this process, we split the expressions or numbers into the same number of parts.
Given:
For the class field trip,
the fourth grades at Jefferson Elementary School need to take buses.
Each bus fits 55 students,
and there are 200 students in fourth grade.
The number of buses,
= 200/55
= 3.63
≈ 4.
Therefore, the need is for 4 buses.
To learn more about the division;
https://brainly.com/question/13263114
#SPJ2
Given the equation [tex]\sqrt[2]{x-5} = 2[/tex], solve for x and identify if it is an extraneous solution.
x = 6, solution is not extraneous
x = 6, solution is extraneous
x = 11, solution is not extraneous
x = 11, solution is extraneous
Answer:
x = 6, solution is not extraneous
Step-by-step explanation:
If you go and plug in 6 then the equation works well and there are no extraneous solutions.
which rectangle is similar to a rectangle 12 inches wide and 18 inches long
Answer:
do u have pics?
Step-by-step explanation:
Why was the ancient Egyptian teenager confused?
Answer: her daddy was a mummy
Step-by-step explanation:
Which of the following slopes of a line passes through points (2, 3) and (4.7)?
5
2
3
Answer: 2
Step-by-step explanation:
7-3/4-2 = 4/2 = 2
(MARKING BRAINLIEST) 100 points
Answer: 1) $0.76 per serving of pumpkin pie
2) 64 people
3)
1 1/3 cup sweet potatos
2 tablespoons + 2 teaspoons of white sugar
1 egg
1/4 teaspoon of salt
2 tablespoons of butter
2 tablespoons + 2 teaspoons of milk
1/4 teaspoon of vanillia
2 tablespoons + 2 teaspoons of brown sugar
1 tablespoon + 2 1/3 teaspoons flour
2 tablespoons + 2 teaspoons of peacans
Step-by-step explanation:
1) the total cost of the ingredients needed to prepare a pumpkin pie = $1.50 + ($2.59 / 6) + ($5.99 / 6) + $1.25 + ($3.79 / 2) = $6.075
if we cut 8 servings per pie, then the cost per serving = total cost of the pie/number of servings = $6.075 / 8 = $0.759375 ≈ $0.76 per serving of pumpkin pie
2) 1lb=16oz
24/6=4
4x16=64
Answer:
0.76 per serving of pumpkin pie
2) 64 people
Step-by-step explanation:
What is the slope-intercept equation of the line below?
Answer:
B y= -5/4x+3
Step-by-step explanation:
What if it is asking you to divide and not multiply?
Answer:
Then you divide :)
<3 Enjoy,
Dea
Please help me fast!!!.
Ruben is touring New York City with his family. They want to visit the Empire State Building, Central Park, and Times Square before their dinner reservations at 8:00 P.M. They want to spend 1 hour and 30 minutes at the Empire State Building, 3 hours in Central Park, and 45 minutes in Times Square. What is the latest time Ruben's family can start their tour in order to make it to dinner on time?
Include A.M. or P.M. in your answer. Please help me fast!!!
Answer:
2:30pm
I hope this helps :)
3. Tarzan went to the plant nursery and bought a tree that was initially 90 feet tall for his monkey friends to climb on.
After planting the tree, Tarzan made a table to record the height, h, of the tree, t years after it was planted. “Zero” is the time when he planted the tree.
t 0 1 2 3 4
h 90 105 120 135 150
(a) Use words to describe the relationship between the height of the tree and the number of years since it was planted.
(b) Write a two-variable equation to illustrate the relationship between the height of the tree and the number of years since it has been planted.
Answer:
ok im convuzed how do you buy a 90ft tree cuz that sounds fun
Step-by-step explanation:
pls lemme know
Santiago starts a savings account with $20. Each month he deposits $15 more into the account. Santiago wants to save a least $80. Write an inequality that represents this situation.
Answer:
$20 + $15m ≥ $80
Step-by-step explanation:
He starts off with $20.
He adds $15 each month, so $15m.
He wants to save at least $80, which means greater than or equal to $80. So, you use this symbol: ≥
Put it all together.
$20 + $15m ≥ $80
Hope that helps.
Duff says that 10 times as many as 5 tens is 5 thousands. Is duff correct
Answer: My guess is hes incorrect, its 500 because we know 5 tens is 50 and if we make it ten times 50 it is 500
Answer:
No he’s not correct
Step-by-step explanation:
So he says that 10 times 5 tens is 5 thousands. 5 tens is 50. So if you do 10 times 50 it’s only 500 not 5 thousand. At least this is what I think you mean