What's the only room from which no one can enter or leave

Below is the sum of symbols in each row and column in the figure. Analyzing the figure, can you find out the value of the symbols?

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

Who am I?

Four children having five rocks each were playing a game in which they had to throw the rock at a particular solid area in the water. Child 1- Succeeded in throwing three rocks at a solid area but one of the rocks sunk. Child 3 - His aim was so bad that all rocks got sunk. Child 4- He was awesome and none of the rocks got sunk. Child 2 - Was the winner but was struck by a rock in the head and died. Who killed Child 2?

On a bus, there is a 26-year-old pregnant lady.
A 30-year-old policeman.
A 52-year-old random woman.
And the 65-year-old driver.

Who is the youngest?

Can you find the largest Three-digit number whose sum is 14 and whose square is less than 5,00,000?

You can see it everyday, But cannot touch it at will. What is it?

Once while in his court, King Akbar asked Birbal to write something on a wall that makes one sad when read in good times and makes one happy when read in sad times.

He took only a few moment and wrote something that fit the requirements. What did he write?

Railroad Crossing, look out for the cars. Can you spell that, without any R's ?

Andrew sees a very rare bird named "Ruppell's vulture". Soon Andrew was dead. Can you explain the mystery, Mr. Sherlock?