What is an advantage of a nuclear reactor over a power plant that uses fossil fuels?
A. Nuclear reactors do not produce any hazardous waste product.
B. The fuel for nuclear reactors can be used without any processing.
C. Nuclear reactors do not produce greenhouse gases.
D. A nuclear reactor is much more economical to build.

The human body stores chemical energy from digested food. some of the chemical energy is converted into mechanical energy when the body moves. which statement best supported by this information

Could someone . i have tried to solve myself but my calculation is off

As you are trying to move a heavy box of mass m, you realize that it is too heavy for you to lift by yourself. there is no one around to , so you attach an ideal pulley to the box and a massless rope to the ceiling, which you wrap around the pulley. you pull up on the rope to lift the box. use g for the magnitude of the acceleration due to gravity and neglect friction forces. once you have pulled hard enough to start the box moving upward, what is the magnitude f of the upward force you must apply to the rope to start raising the box with constant velocity? express the magnitude of the force in terms of m, the mass of the box.