Decode this picture on T-Shirt and tell what it says ?

Find out the missing number in the picture attached:

In four steps you need to move the word 'cold' From 'warm' by replacing one alphabet at a time such that every word formed at each step is acceptable in English Dictionary.

Can you place three balls such that the equation shown in the picture holds true?

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

There are two candles. Both will only burn exactly for an hour. How will you use these two candles to measure forty-five minutes?

Can you replace the X (both small and big x) with the numbers between 1 to 19 such that all the rows of 3 numbers between X (big x) sum to 23?

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 prime number.
The double of myself is equal to the square of me.

which number am I?

I know a ten-letter word in the English language which can be typed using only the top rows of the computer keyboard.