Answer:
1 hour and 20 minutes
Step-by-step explanation:
-7
f(3) = 2(3)+3 = 9
g(4) = 2^4 = 16
9 - 16 = -7
80
x y
2 = 20
8 = x
cross multiply( 8*20)/2
= 4 * 20
= 80