If the effects of atmospheric resistance are accounted for, a falling body has an acceleration defined by the equation a = 9.81[1-v^2(10^{-4})] m/s^2, where is v in m/s and the positive direction is downward. If the body is released from rest at a very high altitude, determine (a) the velocity when t = 5 s(b) the body’s terminal or maximum attainable velocity (as t→[infinity]).

It's a snowy day and you're pulling a friend along a level road on a sled. you've both been taking physics, so she asks what you think the coefficient of friction between the sled and the snow is. you've been walking at a steady 1.5m/s, and the rope pulls up on the sled at a 32 ∘ angle. you estimate that the mass of the sled, with your friend on it, is 65 kg and that you're pulling with a force of 80 n .