A 12-Kg Crate Rests on a Horizontal Surface and a Boy

Multiple Choice

A 12-kg crate rests on a horizontal surface and a boy pulls on it with a force that is 30° below the horizontal.If the coefficient of static friction is 0.40, the minimum magnitude force he needs to start the crate moving is:

A) 44 N
B) 47 N
C) 54 N
D) 56 N
E) 71 N