The initial speed of the rocket is u = 11 m/s
The mass of the rocket is m = 1.3 kg
The kinetic energy of the rocket will be

The kinetic energy will be converted to potential energy

Also, the potential energy will be

Here, the acceleration due to gravity is g = 9.8 m/s^2
The height up to which the rocket will reach is h.
Substituting the values , the height will be
![undefined]()
78.65