. Is there net work done on an object at rest or moving at a constant velocity?
WHICH ONE ???

If an object is moving with a constant velocity, then by definition it has zero acceleration. So there is no net force acting on the object. The total work done on the object is thus 0 (that's not to say that there isn't work done by individual forces on the object, but the sum is 0 ).

atomic = no of protons.

mass number-atomic number = neutron number

muscle endurance

explanation:

i can do 50 in a row ( but i get so tired after that)