Why is Saturday stronger than Monday?

I am five letter word that is under you.
If you remove my 1st letter, then I am over you.
If you remove my 1st and 2nd letters then I am all around you.

Who am I?

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

A man wants to cross the pit of fire which is 25 feet in length and he has 2 planks(fire resistant) 19 feet in length. How can he cross the pit of fire alive?

Find the next number in the series?
2, 12, 36, 80, 150, 252, 392, _ ?

Can you solve the below tricky visual equation?

Can you count the number of triangles inside a triangle?

Place the numbers from 1 to 9 in the circles in a manner that each side of the triangle sums up to 17.

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

Who is that with a neck and no head, two arms and no hands? What is it?