For 2 divide, then do the subtraction and multiplication..
6 / 2 = 3
1-2+15=16
for 3, multiply inside of the parenthesis..
8x2=16 and subtract 3.
16-3=13..
The answer for this question will be A !! I might be wrong and I’m sorry but I’m saying A
I’m not 100% sure but part a is 144 part b is the composite