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2 years ago

9

a radioactive substance has a half-life of 2 seconds. A scientist begins with a sample of 20 grams. How much of the substance re

mains after 8 seconds?

1 answer:

s344n2d4d5 [400]2 years ago

5 0

Answer:

1.25 g

Step-by-step explanation:

you start with 20g at 0 seconds.

divide by half after 2 seconds and you have 10g.

at 4 seconds you have 5g.

at 6 seconds you have 2.5g.

at 8 seconds you have 1.25g.

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