What does this below rebus puzzle mean?

What number does the below three word/phrase identify and why?
1. Deck
2. Year
3. Singing in the Rain

Replace the question mark in the picture below.

A number can be multiplied by multiple of nine
i.e 9 18 27 36 45 ...

and the resulting number consist of only one digit.

Can you identify the number ?

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?

What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

I can turn polar bears white.
I can make anyone dance.
I can make everyone cry
I can make your hands clap
I can make you thin.
I can make you smile.
I can make you smile

Can you guess the riddle?

I am a word that begins with the letter “i.” If you add the letter “a” to me, I become a new word with a different meaning, but that sounds exactly the same. What word am I?

Which Burger Is Different in below image?