Which object will experience the least amount of gravitational attraction toward Earth? a 5-gram pencil

a 40-gram eraser

a 75-gram calculator

a 380-gram cup

Yes, endothermic means it turns cold. and some chemical changes include change of tempature.

The answer is c - the principal of original lateral continuity. 

The answer to your q the total mass is 73

Remember that rust prevented by placing a sacrificial electrode in electrical contact with the iron. the sacrificial electrode must be composed of a metal that  oxidizes  more easily than iron (that is, it must be below iron in table 18.1).