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

What Time Should the last watch show in the below figure?

You have a basket containing ten apples. You have ten friends, who each desire an apple. You give each of your friends one apple.
Now all your friends have one apple each, yet there is an apple remaining in the basket.
How?

I never stop running even when I standstill. If I am formed by joining two identical bodies together, can you guess who I am?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?

What is the longest word in the dictionary?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

In Greek mythology, the Sphinx sat outside of Thebes and asked this riddle of all travellers who passed by. If the traveller failed to solve the riddle, then the Sphinx killed him/her. And if the traveller answered the riddle correctly, then the Sphinx would destroy herself. The riddle:

What goes on four legs in the morning, on two legs at noon, and on three legs in the evening?

Oedipus solved the riddle, and the Sphinx destroyed herself.

What is the Surname of Barbie Doll?

1 rabbit saw 9 elephants while going to the river. Every elephant saw 3 monkeys going toward the river. Each monkey had 1 parrot in each hand. How many animals are going towards the river?