Motion in fields - Space Shuttle orbiting the Earth

[KrisG]

I don;t really know how should I "tackle" this problem. The only thing I got is the answer for a) i) 1.9 * 10^11 J.

It's a problem from IB Oxford Study Guide.
http://img59.imageshack.us/img59/4986/fiz6.jpg

I would be very grateful if You could help :)
Thanks!

 

[tms]

Start with a.ii. What equations describe uniform circular motion?