As you push a cereal box across a tabletop, the sliding friction acting on the cereal box

a.) acts in the direction of motion.

b.) equals the weight of the box.

c.) is usually greater than static friction.

d.) acts in the direction opposite of motion.

2.) projectile motion is caused by

a.) the downward force of gravity.

b.) the initial forward velocity.

c.) a final vertical velocity.

d.) the downward force of gravity and an initial forward velocity.

Aballoon is rising vertically upwards at a velocity of 10m/s. when it is at a height of 45m from the ground, a parachute bails out from it. after 3s he opens his parachute and decelerates ata a constant rate 5m/s.when. (a) what was the height of the parachutist above the ground when he opened his parachute? (b)how far is the parachutist from the balloon at t=3s? (c)with what velocity does the parachutist hit the ground? (d)after how long does the parachutist hit the ground after his exist from the balloon?