<span>5(14 - 2)^2 ÷ 2
= </span><span>5(12)^2 ÷ 2
</span><span>= 5(144) ÷ 2
= 720</span><span> ÷ 2
= 360</span>
The mass of cesium left afer 120 years if the original mass of cesium is 8640 with an half-life of 30 years, is 540 grams.
<h3>What is half-life?</h3>
This can be defined as the time taken for half the amount of a radioactive substance to decay.
To calculate the amount of cesium left after 120 years, we use the formua below.
Formula:
- R' = R/(
)............. Equation 1
Where:
- R = Original amount of Cesium
- R' = New amount of cesium
- T = Total time
- t = Half-life
From the question,
Given:
- R = 8640
- T = 120 years
- t = 30 years
Substitute these values into equation 1
- R' = 8640/(
) - R' = 8640/
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- R' = 8640/16
- R' = 540 grams.
Hence, The mass of cesium left afer 120 years is 540 grams.
Learn more about half-life here: brainly.com/question/25750315
Answer:
I can't see the question
its too small can you type it out?
Step-by-step explanation:
(a) If we let x be the number of miles and y be the total cost, the equation for relating the number of miles and the total cost would be,
y = 0.4x + 48
(b) If the rental cost is 60,
60 = 0.4x + 48
The value of x from the equation is 30.
(c) You may prepare the table of values by allowing x be any number and then solve for y until we arrive with an answer for y being equal to 60.
Step-by-step explanation:
D) 12 in3
How to get the volume
length x width x height
in this case it be
base x height