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.
It allows electrons to flow from the anode to the cathode.
Coffee keeps you awake due to the caffeine in it. Caffeine is considered a psychoactive drug which energizes people by releasing a chemical in the body.
You would need exactly 50 molecules of glucose.
Answer:
to determine of it is a solid liquid or gas.
Explanation:
The melting point is the temperature at which a substance converts from a solid state to a liquid state.