Can you replace the question mark with the correct number?

Jigsaw captured 100 people and make them stand in a circle and all these people are labelled as Person1, Person2, Person3... Person100. He made them play a crazy game in which Person 1 shot Person 2 and pass the gun to the next person and so on until one stands alive.

Which person will survive in the end?

Why do people go to bed?

What question can you never answer yes to?

I have Rs.50 and I spend it in the way as below.

Find The Next Number in the series:

12 13 15 17 111 113 117 119 123 ?

What has many keys but can’t open a single lock?

When a clock is observed, the hour hand is at a minute mark and the minutes hand is six minutes ahead of it.

When the clock is observed again after some time, the hour hand is precisely on a different minute mark and the minute hand is seven minutes ahead of it.

Can you calculate how much time has elapsed between the two observations?

Can you count the number of quadrilaterals in the picture below?

It has horns but can’t beep. It is like to bleat but It is not a sheep. What is it?