Finding orbital speed and period for astronauts around the moon

[XodoX]

Hey guys, I got the following problem.

Whenever two Apollo astronauts were on the surface of the moon, a third astronaut orbited the moon. Assume the orbit to be circular and 100km above the surface of the moon, where the acceleration due to gravity is 1.52 m/s. The radius of the moon is 1.70 x 10⁶. Determine the astronauts orbital speed and the period of the orbit.

It seems east, btu I still have no idea how to get started on this one

 

[The Bob]

What equations do you know that could give you a starting point?

The Bob

 

[XodoX]

None. got all m or T in it, so thatös not going to work.

 

[The Bob]

What is the equation Newton's second law in circular motion?

The Bob

 

[XodoX]

Thats a= v²/r.

You mean v= square root of a * r ? Ok, I didn't think of that then. But what about the period?

 

[The Bob]

Well that is answered for you in the question:

Assume the orbit to be circular [...]

This enough of a hint?

The Bob