a parachute designer is task with designing a round parachute for a human that weighs 160lbs. the user wants to descend at a rate of 4.5 meters per second. given that the coefficient of drag is .75 and the air density is 1.22 kilograms per cubic meter. what is the area in meters squared of the parachute that the designer will have to construct?

Asolid cylinder and a cylindrical shell have the same mass, same radius, and turn on frictionless, horizontal axles. the cylindrical shell has light-weight spokes connecting the shell to the axle. a rope is wrapped around each cylinder and tied to blocks of equal masses that are held the same height above the ground. both blocks are released simultaneously. the ropes do not slip. which block hits the ground first? or is it a tie?