Can you count the number of squares in the given picture?

There are three light switches outside a room. One of the switches is connected to a light bulb inside the room.
Each of the three switches can be either 'ON' or 'OFF'.

You are allowed to set each switch the way you want it and then enter the room(note: you can enter the room only once)

Your task is to then determine which switch controls the bulb?

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

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

If I put in one bird per cage, I have one bird too many. If I put in two bird per cage, I have one cage too many. How many cages and birds do I have?

What does below chemistry rebus means?

Can you place six matchsticks in a manner that each of the matchsticks is in touch with the other five matchsticks?

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

What's a single-digit number with no value?

A lion and its tamer are standing inside a cage that measures 1 unit in radius. Both of them can effortlessly run at the speed of 1 unit maximum.

1) Suppose the lion is hungry, will he be able to eat up the tamer?
2) If yes, how long can the tamer survive?