$9,300
First, multiply your beginning amount by the percent of interest: 3,000x0.07 = 210
Then, multiply your interest times the number of years:
210x30 = 6,300
Add you interest to your initial amount:
3,000 + 6,300 = 9,300
I'll assume those are squares. We know D is an identity:

Dividing through by


That's A.
Dividing the original through by


Not quite B, wrong sign on tangent.
C has the wrong sign on cosine squared as well.
Identities: A & D
I think you have to divide
The answer is 8.
3 times 2 times 8 equals 48.