The water in the river moves with the speed 0.523 km/h. Alice and Bob can swim with the speed 2.62 km/h with respect to the water. They want to get from point A on one bank of the river to point B directly across on the other bank. Alice swims along the straight line AB, while Bob swims with a velocity perpendicular to the river and lets the flow take him some distance downstream. After that, he walks to point B along the river. What is the speed of his walk if he reaches point B at the same time as Alice

Scientific classification

Answer///air resistance,drag;

W= fd
where f is an applied force and d is the distance over which it is applied. when a parachuting skydiver is at constant velocity, he is experiencing "terminal velocity", the point at which his acceleration down is canceled out by air resistance. that means that the resisting force of the air is equal to his weight, but in the opposite direction. with this, we can solve for the work done by the force.
w = fd
w = (92.0)(9.81 m/s^2) (325)
w= 2.93 x 10^5 j
the value for work in this case is positive because it is pushing up on the skydiver, who has a downward force of gravity.
therefore the answer is 2.93 x 10^5 j