Hi everyone! Here is my question!

The orbit of Uranus around the sun is nearly a circle radius 2.87 x 10^12 metres.

The speed of Uranus is approximately constant at 6.80 x 10^3 m/s. The mass of Uranus is 8.80 x 10^25 kg.

a) Name the force that causes centripetal acceleration. (My answer, which I think is correct, is Fg)

b) Determine the magnitude of this force. (Unsure as to which equation I am supposed to use?)

c) Calculate the orbital period of Uranus, both in seconds, and in Earth years.

Merci to all who can help :-D