Two tractors pull against a 1000 kg log. If the angle of the tractors' chains in relation to each other is 18.0° (each 9.0° from being parallel with the log) , and each tractor pulls with a force of 800 N, what forces will they be able to exert?
A. 250 N
B. 1520 N
C. 1580 N
D. 1600 N

I'm 80% sure it's C but I don't know how to go about calculating the answer. Any help is appreciated.