Which flower has two lips?

A famous swimmer can swim downstream in a lake in exactly 40 minutes with the lake current.
He can swim upstream in that lake in exactly 60 minutes against the lake current.
The length of the lake is 2 km.

How long he can cover the distance of one side at a still lake with no current?

Can you place six X (crosses) in below board without making three in a row in any way ?

What breaks yet never falls, and what falls yet never breaks?

Which is the rope you never skip with?

A new Engineering building containing 100 offices had just been completed. John was hired to paint the numbers 1 to 100 on the doors. How many times will John have to paint the number nine (9)?

John replied, when asked how old he was. In 2 years he will be twice as old as he was five years ago.' How old is he ?

If you had a pizza with crust thickness 'a' and radius 'z', what's the volume of the pizza?

I have lakes with no water, mountains with no stone and cities with no buildings. What am I?

I have nine bottles of wine and one of the nine bottles is poisoned.
I need to find the poisoned bottle with two facts
(1) Poison is deadly, only a sip will cost death
(2) I have two mice to do so.

How should I do it?