First things first.
It says the length is 175. Therefore:
A. The length 4 times plus 10
(175 x 4) + 10
= 700 + 10
= 710 ft
B. The length 3 times plus 10 laps
(175 x 3) + (500 x 16) //because one lap is 500 ft and it asks you for 16 laps
= 525 + 8000
= 8525 ft
C. The length 6 times plus 25
(175 x 6) + 25
= 1050 + 25
= 1075 ft
Hope it helps!