Answer
See the motion graph below.
Work Step by Step
In this problem, we do not have enough information about the rocket but we can assume that it is accelerating upward since we know it must start at zero speed.
So, the initial speed is zero, and the rocket speeds up at a constant rate while moving upward. This means that $\left(a_y=+\;\rm constant\right)$.
And hence, the motion diagram must be as seen below.
