How many triangles are there on the puzzle below?

Buy me, smell me or deliver me, I do not change.

Who am I?

Christina is older than Kareena and Karishma. Katrina is older than Karishma and younger than Kareena. If Kareena has a brother named John, who is older than Christina, who's the youngest?

Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

A man is found dead with a knife in his back When the investigation is done. A chair lays beside him and the forensic team finds moisture around the body.

If he committed suicide, how did he do it?

There is a brick of gold and a brick of iron in a boat (both 10-inch blocks), if they are both dropped into the water which will make the water level higher?

What is the word or phrase?

Imagine you are in a room with no windows or doors. How will you get out?

A finger goes in me. You fiddle with me when you're bored. The best man always has me first. What am I?

Jenifer and Jesica are having a conversation.

Jenifer: I am definitely not over 30.
Jesica: I am 28 and you are surely 5 years older to me at least.
Jenifer: No, you are at least 29.

You are told that both of them are lying throughout in the conversation. Can you find their respective ages?