Replace the question mark with the number below given a simple math problem.

We have shown you a regular water barrel as below. Without using any measuring device can you check if the barrel is more than half-filled or less than half-filled?

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

2, 3, 5, 9, 17, _ What is the next number in the sequence?

There is a wide field of corn. A goose finds its way into the field and starts running. Can you find out till which point the goose can run into the field?

Your job is to measure 45 minutes if you have only two cords and matches to light the cords.

1. The two cords are twisted from various materials, so their different segments can burn at different rates.
2. Each cord burns from end to end in exactly one hour.

Describe your way of measuring the 45 minutes.

A family is trapped in a jungle. There is a bridge which can lead them to safety. But at one time, the bridge can only allow two people to pass through. Also, all of them are afraid of the dark and thus, they can't go alone.

Father takes 1 minute to cross, the mother takes 2 minutes, the son takes 4 and the daughter takes 5 minutes. While crossing the time taken will be according to the slower one. How can they all reach the other side in the minimum possible time?

Using eight eights and addition only, can you make 1000?

Can you fill the blank with the correct number?

6 30 870 756030 _____

On a windy rainy night , I was driving in my car.
When i reach the bus stand , i see three people waiting for the bus.

1. An old lady who needs an immediate medical attention
2. My Best Friend
3. Girl whom i love from childhood

My car is a two seat, so can you tell me , what i have done in this situation ?