Explanation:
I believe part of the question is missing. can you please check on it?
is there a part where the mass of the object is mentioned?
The answer here would be the force of gravity Hope I could help! :)
A. Resistance R is a fraction of voltage over current:

b. The power of the toaster P is a multiplication of voltage:

c. 1 kW = 1000W then:
They differ because they are transverse wave. That is their direction of travel is perpendicular to its vibrations. I'm not that sure though. Hope you get it right :).....