Answer
Initially the velocity increases when in contact with rubber band but when it leaves the rubber band it starts decelerating due to gravitational force.
Work Step by Step
Given a paper weds launched straight up using a rubber band. When the per weds still in contact with rubber after launch its velocity increases but as soon as it leaves the rubber contact it is under influence a gravity which acts downwards hence it starts decelerating till its highest point. At highest point its velocity becomes zero. The corresponding motion diagram A given below.
