Which Interaction does not take place due to field forces?
OA. Interaction between protons and electrons
OB.
Interaction between a ball in flight and the earth below it
C.
interaction between Mars and the Sun
OD. interaction between a pen and paper while you write

The experiments with static charges were done by:

At very high pressures, gases become and will eventually a) more dense; become hotter b) more dense; change to a liquid or solid c) less dense; combust d) less dense; turn into a liquid

Does anyone know how to solve this problem? i really need . i made an attempt but i just cant get it. a metal rod is 25.000 cm long at 25.0 degrees celsius. when heated to 102.0 degrees celsius, it is 25.054 cm long. what is the coefficient of linear expansion for this metal.