Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

A patient was diagnosed with some ailment. He was given five different tablets to take at night at an interval of 15 minutes.

How long will it take the patient to consume all the five tablets?

How can a man go eight days without sleep?

What number comes next in this sequence:
7 8 5 5 3 4 4 _

A tree doubled in height each year until it reached its maximum height over the course of ten years. How many years did it take for the tree to reach half its maximum height?

You bought me for dinner but never eat me. What am I?

What 8 letter word can have a letter taken away and it still makes a word. Take another letter away and it still makes a word. Keep on doing that until you have one letter left. What is the word?

I cannot talk, but I always reply when spoken to. What am I?

What famous saying does this rebus mean?

COME SERVED <---
COME SERVED
COME SERVED
COME SERVED
COME SERVED

I am never scared but became petrified and can’t live in a house but would die to make one. What am I?