An electric train is going south which way is the smoke blowing

The of a machine determines its "usefulness." a. input force b. output force c. mechanical advantage

What is the temperature in degrees celsius of a substance with a tempature of 49k

Awheel of mass 48 kg is lifted to a height of 0.8 m. how much gravitational potential energy is added to the wheel? acceleration due to gravity is g = 9.8 m/s2. a. 30.4 j b. 3.1 j c. 297.9 j d. 11,321 j