What is the next number in this matchsticks series riddle?

Things are just as they seem, right? Well, check again.
Can you count the number of tigers in this picture ?

What is full of holes but still holds water?

Count the number of triangles in the picture below:

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?

Can you count the number of squares in the figure below?

What is the unique property of the following words ?
* Revive
* Banana
* Grammar
* Voodoo
* Assess
* Potato
* Dresser
* Uneven

What makes this number unique: 8,549,176,320?

Usually, a boxing match consists of twelve rounds. In a particular friendly match between two heavyweights, the match was finished in the ninth round itself as one of the boxers knocked out the other one.

But, in that fight, no man threw even a single punch.

How can this be possible?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?