Relative pronoun and verbs

by Fahrul
(Indonesia)

Hey Ola, how are you doing? I hope you don't mind answering my question.

A) Which one is correct and why?
1. Mahatma Gandhi whom is considered ....
2. Mahatma Gandhi who is considered....

Well, I'd say "whom" is the correct one here, but I don't know. Just confused.

B) What's the weather like today???
a. it is raining
b. it is to rain
c. it is rain

This time, I'd place my bet on B (it is to rain)

C) I have confusion on the use of (S + to be + inf to + V)

Could you please explain that to me??

Anyway, are my answers correct?

thank you