A medical cyclotron used in the production of medical isotopes accelerates protons to6.5 MeVMeV. The magnetic field in the cyclotron is 1.9 TT.

What is the diameter of the largest orbit, just before the protons exit the cyclotron?

A proton exits the cyclotron 1.0msms after starting its spiral trajectory in the center of the cyclotron. How many orbits does the proton complete during this 1.0 msms?