Who always enjoys poor health?

Solve the counting riddle by identifying the number of triangles in the given picture.

Count the squares in the matchstick puzzle below?

I have eight fingers and two thumbs but I do not live. What Am I?

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

John bought 150 chocolates but he misplaced some of them. His Father asked him how many chocolates were misplaced.
He gave the following answer to him:
If you count in pairs, one remains
If you count in threes, two remain
If you count in fours, three remain
If you count in fives, four remain
If you count in sixes, five remain
If you count in sevens, no chocolate remains.

Can you analyze the statements and tell us how many chocolates were lost?

I am eight letters long - "12345678"
My 1234 is an atmospheric condition.
My 34567 supports a plant.
My 4567 is too appropriate.
My 45 is a friendly thank-you.
My 678 is a man's name.

What word am I?

The person who makes it has no need for it; the person who buys it has no use for it. The person who uses it can neither see nor feel it. What is it?