D because 1.29 plus 2.75 is 4.04(the money that he used to make the case) and subtract that with $12 and you get $7.96 as the profit.
3/10=4/x
3x=10(4)
3x=40
x=13.33
We know:
and
These expressions have an 
term in common. We can combine them if we can find forms of the expressions in terms of :
Now, because 
(by the reflexive property), we can write:
This is our answer, A.
Answer:
(a) is 4*C and (B) is 16*C
