Answer:

Explanation:
M = Mass of Earth
G = Gravitational constant
R = Radius of Earth
The acceleration due to gravity on Earth is

On new planet

Dividing the two equations we get

The acceleration due to gravity on the other planet is 
Supposing the runner is condensed to a point and moves upward at 2.2 m/s.
It takes a time = 2.2/g = 2.2/9.8 = 0.22 seconds to increase to max height.
Now looking at this condition in opposite - that is the runner is at max height and drops back to earth in 0.22 s (symmetry of this kind of motion).
From what height does any object take 0.22 s to fall to earth (supposing there is no air friction)?
d = 1/2gt²= (0.5)(9.8)(0.22)²= 0.24 m