A battery used in a mechanical toy stores 10,000 kJ of energy. The toy 5 points expends 7,500 kJ of energy before the battery runs out of energy. What is
the efficiency of the system?

The diagrams show objects’ gravitational pull toward each other. which statement describes the relationship between diagram x and y? gravity attracts only larger objects toward one another. gravity attracts larger objects only if they are close to one another. if the masses of the objects increase, then the force between them also increases. if distance between the objects increases, then the amount of force also increases.

  the mississippians were considered to be  horticulturalists, which means they were

What does the symbol (–hfus) indicate in a phase change?