How difficult it is to change an objects motion. Think of a tablecloth; it takes energy to move it from underneath objects on the table, and it takes energy to move the objects themselves on the table.
Answer:
B
Explanation:
As the distance between the planets and the sun increases, the period of revolution increases as well. The period of revolution is how long it takes for a planet to revolve around the sun. So, because the planets farther from the sun have a higher period of revolution in earth years, this also means they have longer actual years, which means the answer is B.
Answer:
the results of an investigation thank me later
Explanation:
Organic chemical compounds as recommended by the (IUPAC)
Answer:B) a reactant that undergoes reduction
Explanation:
Oxidation reaction is defined as the reaction in which a substance looses electrons. The oxidation state of the substance increases during oxidation.
Reduction reaction is defined as the reaction in which a substance gains electrons. The oxidation state of the substance gets reduced during reduction.

Overall reaction: 
The substance M which itself gets oxidized, reduces other and is called as reducing agent. The substance N which itself gets reduced, oxidizes other and is called as oxidizing agent.