Calculating Work and Power: Solving a Tractor Pull Problem

[bob24]

Homework Statement

A tractor pulls a wagon with a constant force of 700N at a constant speed of 20.0 km/h.
a) How much work is done by the tractor in 3.5min
b) What is the tractor's power output?
ANSWERS: a)8.16 x 10^6 J//b) 3888.8 watts
2. Relevant equation
P=W/t or P=Fv

The Attempt at a Solution

P=Fv
P=700N x 20.0
P=14000J

Pt=W
14000W x 210seconds=W
W=2940000J

I've been trying for over an hour now and I just can't get the answer. Any help will be greatly appreciated.

 

[rl.bhat]

Convert km/h to m/s.

 

[bob24]

Convert km/h to m/s.

I realized it about 5 seconds before you posted haha. Thank you very much!