need help with physics

Question

You are asked to pull a 120.0 kg crate at a constant velocity across a level concrete floor with an effective kinetic coefficient of friction = 0.7 . How much work will you need to do to pull the crate 15.00 m?

a) 18000 J

b) 15340 J

I got 17640 J but that's incorrect.

Answer 1

First, find the weight of the crate. F = ma, where a is the acceleration of gravity.

The friction force is then the weight * the coefficient of friction

The work done is the friction force times the distance.

The answer I get is not one of the choices---perhaps you could make sure the problem is copied correctly