Answer:
Explanation:
velocity of ship with respect to water = 6.5 m/s due north

velocity of water with respect to earth = 1.5 m/s at 40° north of east

velocity of ship with respect to water = velocity of ship with respect to earth - velocity of water with respect to earth



The magnitude of the velocity of ship relative to earth is
= 5.66 m/s
if we are walking on a perfectly smooth ground which has no friction our force would simply cancel out the force reverted by the ground and we would fall.
We need it to help push out feet off the ground
Hope those helps :)
Given required solution
M=10kg W=? W=Fd
v=5.0m/s F=mg
t=2.40s =10*10=100N
S=VT
=5m/s*2.4s
=12m
so W=12*100
W=1200J