A plumber charges $75 for each service call and $50 per hour. Which rule gives the cost for x hours of plumbing services?
a. f(x)= 75x-50
b. f(x)= 75x+50
c. f(x)= 50x-75
d. f(x)= 50x+75
The function should read: f(x) = $75.00 + $50x. So, the answer is "d"
