please help!!!

Find the amount of tip on a $75 bill if a 15% tip is left.
A) $ 11.25
B) $ 11.20
C) $ 10.50
D) $12.00

what is the final price for a pair of $39.50 jeans after 5% sales tax has been added?

A)$37.95
B)$40.95
C)$41.48
D)$1.98

What is the final price of $24 sweatshirt if there is a 20% discount applied and then a 7% sale tax added?
A) $22.26
B)$19.20
C)$25.68
D)$20.54