I cannot talk, but I always reply when spoken to. What am I?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?

Using Only Five 5's and any mathematical operator make sum as 37

He runs but never walks. Murmurs, but never talks. Has a bed, but never sleeps. And has a mouth, but never eats?

The more you take me, the more you leave me behind.
Who Am I?

Can you solve the below tricky visual equation?

Be active and find the killer in the picture Riddle below.

It can't be seen, can't be felt, can't be heard, and can't be smelt.
It lies behind stars and under hills, And empty holes it fills.
It comes first and follows after, Ends life, and kills laughter.
What is it?

Which tank will fill first?

There are nine dots in the picture that has been attached with this question. Can you join all the dots by drawing four straight lines without picking up your pen?