milli = 1/1000, so milligams = 1/1000 of a gram.
So:
2000 milligrams * 1 gram/1000 milligrams = 2 grams.
I think the answer is the third one
For better representation, I think the function is written as:
B(x) = 40.00 - 0.08x
This is much more comprehensive. The variable x represents the number of prints. So, if x=40 prints, we replace this to the x in the equation to find the balance B.
B = 40 - 0.08(40)
<em>B = $36.8</em>