Answer:
130
Step-by-step explanation:
Given the equation of the relation as c(h) =50 +20 h where c(h) is the total cost for h hours and h is the number of hours of use, then to find the cost of jet ski if 4 hours were used will be;
c(h)=50 +20 h
c(4)=50 +20*4
c(4)=50 +80
=130
See attached picture:
no cheating thanks <3