4 because if the ship went 40 kilometers south, then 36 north, it would be traveling back to its starting point, so tok would subtract 36 from 40 and get 4. Hope this helped!!
Step-by-step explanation: You divide 45 and 60 then you mutiple the number by 4 then find your answer after you done solved this is how you solve it 45 divided by 60=0.75 mutiply by 4=3
