How many atoms are contained in 0.25 moles of fe

The answer for #3 is c but i don't know why

Arollercoaster car at the top of a hill has potential energy kinetic energy chemical energy light energy

Asap! will give brainiest when a heat wave strikes a region causing more people to run air-conditioning units, electrical demand increases. what needs to be done to meet this increased demand? raising the control rodslowering the control rodsremoving the control rods