Answer:
The answer would be A
Explanation:
WARNING THIS MIGHT BE WRONG BUT WORTH A SHOT
I say "a" because if you look at the problem or equation given
10.50=0.50a+3
10.50 is for the amount of money the had to pay
0.50 is the cost for if they are late for pick-up
the 3 is for the base fee
the amount of mins would be times by 0.50 then that plus 3.
I HOPE THIS HELPED( SORRY IF WRONG)
-dani~