<em>Answer:</em>
<em></em><em></em>
<em>This " / " means or, btw!</em>
<em>Step-by-step explanation:</em>
<em></em><em></em>
<em>⇒Take square root.</em>
<em></em><em> ± </em><em></em>
<em></em><em> or </em><em></em>
<em>Hope this helped you!</em>
Answer:
If y(t) is the mass (in mg) remaining after t years, then y(t) = y(0) (0.5)^{t/T} = 400 (0.5)^{t /4}, where T is the half-life period and y(0) is the amount at t = 0 years (initial).
Then at t = 20:
y(20) = 400 (0.5)^{20 /4} = \text{12.5 mg}
Step-by-step explanation:
Answer:
Thus, option A is correct.
Explanation:
<u>match the proportions</u>
<u>set up a equation:</u>