There is a brick of gold and a brick of iron in a boat (both 10-inch blocks), if they are both dropped into the water which will make the water level higher?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

Can you find the missing number in the third row?
35 20 14
27 12 18
5 2 ?

In particular commonwealth games, a female participant won silver and gold medals for a single event.

How can this be possible?

What does the following BrainBat signifies?

ABCDEFGHIJKLMNOPQRSTUVWYZ

QQQQQQQQQQQQQQQQQQQQQQQQQ.

In a science lab, a petri dish hosts a healthy colony of yeast for an experiment. Now every minute, all the yeast cells divide into two. At noon, there was just a single cell of yeast and at 1:22, the Petri dish was half full. Can you calculate when the dish will be full of yeast?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

Spot the cat in the picture below

A bridge is about to collapse. There are four people P, Q, R and S on one of the sides. Before the bridge collapses, they want to cross it. Now since the bridge is too weak, it can only stand the weight of two people at a time. Also, it is night time and nothing is visible. They have just one torch with them.

Now P takes one minute to cross the bridge, Q takes two minutes to cross, R takes five minutes to cross and S takes ten minutes to cross.

The bridge will collapse in seventeen minutes. How will they be able to cross the bridge before it collapses?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?