I make a loud sound when I’m changing. When I do change, I get bigger but weigh less. What am I?

Two-person want to cross a river. Only one boat is present on the riverside that can carry only one person at a time.

However, they still manage to cross the river. How is it possible?

Find a 9-digit number, which you will gradually round off starting with units, then tenth, hundred etc., until you get to the last numeral, which you do not round off. The rounding alternates (up, down, up ...). After rounding off 8 times, the final number is 500000000. The original number is commensurable by 6 and 7, all the numbers from 1 to 9 are used, and after rounding four times the sum of the not-rounded numerals equals 24.

When it's bad luck to meet a black cat?

What has a ring but no finger?

I possess a head

I flaunt a tail

But I don't have mouth or legs

Can you find out who I am?

Decode below rebus
D
N
A
T
S , D

I have a head like a cat and feet like a cat, but I am not a cat. What am I?

A girl was sitting in her hotel room when she heard a knock on the door. She opened the door and found that a man was standing outside. The man said, "Oh! I am really sorry, I thought this was my room." He then walked through the corridor to the elevator. The girl did not know the man. She closed her door and called security asking them to apprehend the man. What made her suspicious of that man? He might have been genuinely mistaken.

What is the next number in the series?

15 29 56 108 208 ?