Answer:
Step-by-step explanation:
2x^2-2x-12
This has solutions of x=3 and x= -2
I believe you are referring to the half-life formula, which is used to calculate the half-life (when the substance drops to half of its original amount) of radioactive substances. The equation is as follows:

<em>A</em> is the remaining amount
<em>P</em> is the initial amount
<em>t</em> is the time that has passed
<em>h</em> is the half-life of the substance
When plugging values into the equation, make sure that <em>t </em>and <em>h </em>are both measured in the same unit (e.g. <em>t </em>days and <em>h </em>days), as well as <em>A </em>and <em>P</em>.
20 because 16 is greater than 15 and we round the number up.
1/6 = 1 batch, 2/6 = 2 batches and so on
if the factory used 1/2, the factory used 3/6 of a barrel, which equals to 3 batches.
<em>hope it helps :)</em>