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?

John was visiting his friend Jacob. He found out that his friend's wife had just killed a burglar in self-defense.
John asks Jacob about what happened and he told that "His wife was watching television when suddenly the bell rang. She thought that it is her husband Jacob but she found the burglar who attacked her instantly and she got so frightened that she killed the burglar immediately with the knife.
John asked the police to arrest his friend's wife. Why?

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

What breaks yet never falls, and what falls yet never breaks?

What do you call a fish without an eye?

A maths symbol is hidden in the below Bar Graph. Can you decipher it?

What brings you down but never up?

Why blonde cannot dial 911?

Take one out and scratch my head, I am now black but once was red. What am I?

What kind of band never plays music?