Sand is poured into a box so that the box is being filled at the rate of 3 cubic feet per hour. If the empty rectangular box is 5 feet long, 4 feet wide, and 3 feet deep, approximately how many hours does it take to fill the box?	Choose the correct option:
A) 14 B) 16 C) 18 D) 20 E) 22

Rationale: "the volume the box is : length * width * depth = 5 * 4 * 3 = 60 cubic feet . 60 cubic feet / 3 cubic feet per hour = 20 hours . it will take 20 hours to fill the box . the answer is d ."
Answer: D