A person can swim in still water at 12 km/h. If the speed of water 2 km/h, how many hours will the man take to swim back against the current for 10km?	Choose one:
A) 1 B) 4 C) 5 D) 6 E) 7

Rationale: "m = 12 s = 2 us = 12 - 2 = 10 d = 10 t = 10 / 10 = 1 answer : a"
Answer: A