Understaffed Tank Crew

You are the commander of the last surviving tank on the battlefield. Two of your four-person crew have been incapacitated, so you'll only have control of two of the four functions of the tank at any one time. Please note, commander: Although most tanks' gunners aim and shoot,  we had to separate those functions in this tank, in order to get the best armor or bullets or something. Good luck, and do…