What is the next number in the series?

15 29 56 108 208 ?

Find the number of squares in the below picture

I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

Replace each alphabet with the number (1-9) to make the below equation correct.

AB * C = DE - F = GH / I

There was an aeroplane crash, every single person died, but two people survived. How is this possible?

It's a 7-letter word.
If we remove 1 letter from it, it remains the same.
If we remove 2 letters from it, it remains the same.
If we remove 3 letters from it, it remains the same.
If we remove all the letters from it, still it remains the same.
What is it?

It walks on 4 when its young, walks on 2 when it's older, and walks on 3 when its very old?

I look flat, but I am deep. Hidden realms I shelter. Lives I take, but the food I offer. At times I am beautiful. I can be calm, angry, and turbulent. I have no heart but offer pleasure as well as death. No man can own me, yet I encompass what all men must have. What am I?

Do you know who was buried in John's tomb?

If a wheel has 54 spokes, how many spaces are there between the spokes?