Answer:
D
Step-by-step explanation:
To find the number of WHOLE pizzas needed, we need to divide the total number of slices needed (713) by 8 slices. Thus
<em>because we can't order fractional pizza, we need to round up. So we will need 90 pizzas.</em>
<em>Correct answer is D.</em>
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:
Where:
From the question,
Given:
Substitute these values into equation 1
Hence, The mass of cesium left afer 120 years is 540 grams.
Learn more about half-life here: brainly.com/question/25750315