You receive $100 for your birthday. You spend $30 on a tank of gas for your car then spend the rest on as many rounds of miniature golf that you and your friends can play. miniature golf costs 8$ a round. The function f(x)=70 -8x models the remaining amount of money after gas and golf are paid for. What is the most appropriate domain of the function.
A) all integer values of x
B) all positive integer values of x
C) 0 D) 0