Answer:
3.5 in fraction form is 7/2 or 35/10.
The largest mountains on the continents are formed by stress deformation.
This is also know as strain, which is a process that occurs when the intensity of the stress is greater then the internal strength of the rock. This kind of activity, forming of mountains, occurs when to tectonic continental plates with same densities are colliding, so under the pressure, stress, they create, the area of collision is lifting up.
Sunlight is type of EM wave. The intensity of EM follows inverse square law.

This means that the intensity at a distance that is n times greater will be n^2 times smaller.
Now we set this equation to be equal to 9 and we solve it for n:

The intensity is 9 times greater at a distance that is equal to a 1/3 of Earth's distance:
You would need friction and force to move the plates and most likely a strong machine.