The driver of a car moving towards a rocket launching with a speed of 6 ms-1 observed that the rocket is moving with speed of 10 ms-1.The upward speed of the rocket as seen by the stationary observer is nearly

Suppose the car is moving horizontally along positive x-axis with velocity   . Vertical velocity of the rocket is positive y-axis relative to a stationary observer. .velocity of the rocket relative to the car =