What is the next number in the series?

15 29 56 108 208 ?

What has no start, end, or centre?

John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?

Given below is simple addition with a defined pattern pattern:
7 + 7 = 2
8 + 8 = 4
8 + 5 = 1
6 + 9 = 3
10 + 11 = 9

Can you analyze the pattern and find out the answer for:

4 + 9 = ?

A pond had 60 fish, out of which, all but 20 died.
How many fishes are now present in that pond?

Until it is measured, not known. Yet how you miss it when it has gone. What is it?

Alex is stranded on an island covered in forest.
One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, killing the man in the process.

There are cliffs around the island, so he cannot jump off.

How can the Alex survive the fire? (There are no buckets or any other means to put out the fire)

It's a protector.
It sits on a bridge.
One individual can see directly through it, while others wonder what it hides.

What is it?

What 4-letter word can be written forward, backward or upside down, and can still be read from left to right?

When I get multiplied by any number, the sum of the figures in the product is always me. What am I?