Examine the information.

Element A has a half-life of 10 days. A scientist measures out 200 g of this substance. After 30 days has passed, the scientist reexamines the sample. 
How much Element A will remain in the sample

100g

12.5g

50g

25g

is it d?

YES

thank you

To calculate how much of Element A will remain in the sample after 30 days, we need to consider its half-life of 10 days.

After the first half-life (10 days) has passed, half of the original sample will remain. Therefore, 200g/2 = 100g will remain.

After the second half-life (20 days total) has passed, another half of the remaining sample will decay. Therefore, 100g/2 = 50g will remain.

Finally, after the third half-life (30 days total) has passed, another half of the remaining sample will decay. Therefore, 50g/2 = 25g will remain in the sample.

So the correct answer is option D - 25g.

To find out how much of Element A will remain in the sample after 30 days, you can use the concept of half-life. The half-life of an element is the time it takes for half of the original amount to decay.

In this case, the half-life of Element A is given as 10 days. This means that after every 10 days, the amount of Element A will be halved.

So, let's break down the 30 days into three intervals of 10 days each.

After the first 10 days, half of the original 200 g will remain: 200 g / 2 = 100 g.
After the second 10 days, half of the remaining 100 g will remain: 100 g / 2 = 50 g.
After the third 10 days, half of the remaining 50 g will remain: 50 g / 2 = 25 g.

Therefore, after 30 days, 25g of Element A will remain in the sample. Thus, your answer is d) 25g.