I am a type of room you cannot enter or leave. Raised from the ground below, I could be poisonous or a delicious treat. What am I?

They are the five precious gems of an everyday sort and all can be found on a Tennis Court. Who are they?

A California farmer owns a beautiful pear tree. He supplies the fruit to a nearby grocery store. The store owner calls the farmer to see how much fruit is available for him to buy. The farmer knows the main trunk has 24 branches. Each branch has exactly 12 boughs and each bough has exactly 6 twigs. Since each twig bears one piece of fruit, how many plums will the farmer be able to deliver?

What country can make you shiver?

What has no start, end, or centre?

What 5-letter word typed in all capital letters can be read the same upside down?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Name a key which is hardest to turn.

I can be cracked, made, told, and played. What am I?

My friends called me Iron59 because my parents are a chemist and a mathematician. What is my real name?