Answer:
T = 99.51 hour
Explanation:
Mass of Uranus, 
The moon Umbriel orbits Uranus at a distance of 
We need to find Umbriel's orbital period. Let it is T. Using Kepler's third law of motion to find it.

As 1 hour = 3600 s
358244.51 s = 99.51 hour
Hence, Umbriel's orbital period is 99.51 hour.
Explanation:
Given:
Solving for
:

where:

Integrating to get
with initial conditions
:

Integrating to get x with initial conditions x(0) = 0:

When t=T:

