Jen falls out of a tree and lands on a trampoline. The trampoline sags 60 cm before launching Jen back into the air. At the very bottom, where the sag is the greatest, is Jen’s acceleration upward, downward, or zero?

At the very bottom, whnere the sag is the greatest, Jay’s acceleration is upward.

Explanation:

As Jay lands on the trampoline, Jay’s motion was dowward,  the trampoline was opposing his motion and hence, caused him to reach an initial halt position. Afterwards, the trampoline causes Jay to move back into the  air and therefore, the change in velocity vector act in upward direction. The acceleration vector is always align towards the change in velocity vector's direction.