A deuteron (the nucleus of an isotope of hydrogen)

A deuteron (the nucleus of an isotope of hydrogen) has a mass of 3.34*×10-27kg and a charge of +e. The deuteron travels in a circular path with a radius of 6.96 mm in a magnetic field with magnitude 2.50 T.

a) Find the speed of the deuteron.
b) Find the time required for it to make half a revolution.
c) Through what potential difference would the deuteron have to be accelerated to acquire this speed?