Which of these follows from Newton's laws about the energy of a moving object?

Question

anonymous · Answer

The kinetic energy of an object remains the same if friction is absent.

       The total mechanical energy of an object is always constant.

       The mechanical energy remains the same if there are only conservative forces acting.

       The total of all forms of energy is always constant.

anonymous · Answer

friction is what causes things to slow down so i believe its A but here are the newtons laws i focused on  
For every action there is an equal and opposite reaction. 
Every object in a state of uniform motion tends to remain in that state of motion unless an external force is applied to it. 
does that help?

anonymous · Answer

thanks

anonymous · Answer

no problem