The answer is 10mm, I answered this in a previous question.
Answer:
if
and
.
Step-by-step explanation:
We are given
and
.
We are asked to find
.
means 

You only have one pair of like terms, that is the constants.


C= 2000 + 3(2500)
C= 2000 + 7,500
C= $9,500