Answer
The total work that the tugboats do on the tanker is $2.62\times 10^9~J$.
Work Step by Step
Each tugboat pulls with a force that is at an angle of $14^{\circ}$ east of north and $16^{\circ}$ west of north from the direction of motion, as they pull the tanker $0.63km$ toward the north. We can find the work done by one tugboat.
$W_{east} = F~d~cos(\theta)$
$W_{east}= (1.80\times 10^6~N)(630~m)~cos(14^{\circ})$
$W_{east} = 1.10\times 10^9~J$
$W_{west} = F~d~cos(\theta)$
$W_{west}= (1.80\times 10^6~N)(630~m)~cos(16^{\circ})$
$W_{west} = 1.09\times 10^9~J$
$W_{total}= W_{east}+W_{west}$
$W_{total}= (1.10\times 10^9~J) +(1.09\times 10^9~J)$
$W_{total}= 2.19\times 10^9~J$
The total work that the tugboats do on the tanker is $2.19\times 10^9~J$.
