Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

Before the start of the car race, John and Jacob have the same amount of fuel in their car. With this fuel, John can drive for 4 hours while Jacob can drive five hours.
After a time they realize that the amount of fuel left in John's car is 1/4th of the fuel in Jacob's.

For how long they are racing?

Can you decipher the two rows to find the hidden word?

What number do you get when you multiply all of the numbers on a telephone's number pad?

Do you know who was buried in John's tomb?

A cat had three kittens: Snophy, Topsy and Jorden. What was the mother's name?

I look flat, but I am deep. Hidden realms I shelter. Lives I take, but the food I offer. At times I am beautiful. I can be calm, angry, and turbulent. I have no heart but offer pleasure as well as death. No man can own me, yet I encompass what all men must have. What am I?

If,

Akriti = 631
Levis = 521
Sroti = 521
Aneel = 533
Then,
Sunil =?

He runs but never walks. Murmurs, but never talks. Has a bed, but never sleeps. And has a mouth, but never eats?

What is the next number in this matchsticks series riddle?