Answer:
Example of a scientific question:
Does the angle of a ramp change the distance a toy car will travel?
Explanation:
It’s mass number would be 5 as it’s the protons and the neutrons added together
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's ionic because electrictrons are only lost or gained in ionic bonds