The general way to work this out is to solve the general expression for
the remaining quantity versus half-life, using logarithms. But that's not
necessary with these numbers.
Look at the numbers:
-- 3 mg is 1/4 of 12 mg.
-- 1/4 is the product of (1/2) x (1/2).
-- So the 3 mg is what's left of 12 mg after 2 half-lives.
The 26 minutes must be two half-lives.
-- The half-life of that substance is 26/2 = <em>13 minutes</em>.
Go Maggie !
10^-10 in decimal form is 0.000000001. Because the exponent is negative, you move the decimal point ( decimal point is at the end of 0 of the base number 10) 10 place to the right of 10 and u get the answer above. I discarded the 0 later in the answer because now that you've moved the decimal, that 0 have no value. But when forming it in decimal you have to use that 0 or you will get a wrong answer, instead of eight 0's, you will end up with nine 0's.
Answer:
8
Step-by-step explanation:
Answer: The Answer is <u>A: 7.685</u> but then round it up to <u>8</u> on edge