Explanation:
Solids:
Particles stay close together with a pattern
Particles do not flow freely
Definite shape and definite volume
Liquids:
Particles are closer together (compared to gas) with somewhat of a pattern
Particles flow freely
Somewhat strong attractive forces that hold an indefinite shape
Gas:
Particles spread out without a pattern
Particles flow everywhere (they are like kids on a sugar rush)
Weak attractive forces that hold no shape or volume
Indefinite shape and indefinite volume
Not entirely sure what compressibility is so i skipped that one for all of them
The answer is A, friction.
Friction is the force that resists movement, and that's why oil is used as a lubricant and why ball bearings are used for machines that need to move with very little friction(i.e. bike wheels, roller skates, fidget spinners)
Answer B is too vague
C will probably reduce efficiency greatly, but not specifically in a way that turns work into thermal energy.
D is the same as C, except that it places the blame on the person using the machine, not the machine itself.
Hope I helped clear it up for you :)
No, because if their already formed, how would they get bigger
Can't see the structures so we can't answer your question