What building has the most stories?

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

Name a key which is hardest to turn.

Which flower has two lips?

A boy collects white seashells from the sea and brings them home every night. When he has enough of them, he decides to sell them to a trader.

The trader is ready to buy the shells and he asks the boy about the quantity. At this, the boy starts calculating. He has a giant box that contains 3 mini boxes. Two of them have another mini box inside. If the giant box can hold 50 shells, how many brown shells can he sell to the trader?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

Find the number of squares in the below picture

Two guards were on duty outside a barracks. One faced up the road to watch for anyone approaching from the North. The other looked down the road to see if anyone approached from the South. Suddenly one of them said to the other, "Why are you smiling?"

How did he know his companion was smiling?

My thunder comes before the lightning; my lightning comes before clouds; my rain dries all the land it touches. What am I?

A patient was diagnosed with some ailment. He was given five different tablets to take at night at an interval of 15 minutes.

How long will it take the patient to consume all the five tablets?