A shark swims at a rate of 18 feet per second while chasing his prey and then slows down to a rate of 7 feet per second. The shark chases his prey for t seconds and then swims at the slower speed for s seconds, and covers a total distance of 1200 feet. If all traveling is done in the same direction, which equation best describes this information?
A) 1200 (t+s)=25
B) 1200(25)=t+s
C) 1200= 18t+7s
D) 1200= 25 (t+2)