If a wheel has 54 spokes, how many spaces are there between the spokes?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

A 3 digit number is such that it's unit digit is equal to the product of the other two digits which are prime. Also, the difference between it's reverse and itself is 396.

What is the sum of the three digits?

10+10 and 11+11 can give you the same answer.

Explain how?

Why do you find that most of the buildings are deprived of the 13th floor?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

You are given a cube that is made with the help of 10x10x10 smaller cubes summing up to a total of 1000 smaller cubes. You are asked to take off one layer of the cubes.
How many remain now?

In a secret society, a buried chamber can be accessed only via a secret password. The password is seven characters long and comprises of just letters and numbers.

You find a code that can help you in cracking the password. The code says "You force heaven to be empty".

Can you deduce the password from that?

I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

I have branches, but no fruit, trunk or leaves. What am I?