The roof of an apartment building is rectangular and its length is 3 times longer than its width. If the area of the roof is 588 feet squared, what is the difference between the length and the width of the roof?  Choose the correct choice:  A) 28 .  B) 40 .  C) 42 .  D) 44 .  E) 46 .

Rationale: "answer is a : 28 let w be the width , so length is 3 w . therefore : w * 3 w = 588 , solving for , w = 14 , so 3 w - w = 2 w = 2 * 14 = 28"
Answer: A