confused on how to solve this

2. A point charge q = 5 x 10% C and m = 1 x 10" kg travels with velocity v = 30 m/s i and enters a magnetic field: B = 1 x 10-6 T j. a. What is the kinetic energy of the point charge? b. What is the magnitude of the magnetic force that acts on the charge once it has entered the field? c. What is the magnetic force vector exerted on the charge just as it enters the field? d. Why does the magnetic force exerted on the point charge not change it's kinetic energy