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 anyone tell me a word in the English dictionary which has a silent 'z'?

John was gifted a new Hayabusa. He drove x miles at 55mph. Then he drove x+20 miles at 40mps. He drove his bike for 100 minutes. How much distance did he travel?

I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

Buy me, smell me or deliver me, I do not change.

Who am I?

You measure my life in hours
I serve you by expiring
I vanish faster when I am thin
and slower when I am thick
The wind is my energy
What am I?

Count the number of lines in the image below ?

We know that the number 7 is the prime followed by a cube. Which next number is also a prime followed by a cube?

If 21x = 79x, what is the value of x?

They do not possess flesh or feathers or scales or bone
But still, they are blessed with fingers and thumbs of their own.