How many times can you subtract the number two from the number fifty?

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?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

What is in seasons, seconds, centuries and minutes but not in decades, years or days?

I am eight letters long - "12345678"
My 1234 is an atmospheric condition.
My 34567 supports a plant.
My 4567 is too appropriate.
My 45 is a friendly thank-you.
My 678 is a man's name.

What word am I?

Move three sticks of the spiral below to form a square.

Known by all without exception, Forever here, for your protection, Sometimes strong, sometimes weak, Right after the night I come - hot and chic. And while millions of miles away, I always get to you, I find my way. No life around could do without me, Can you guess what I might be?

O_er_t_o_

Complete the missing letters of the given word.

Can it be possible to build a house that has all its four walls facing towards the South?

It's pretty hard to give up.
If you remove a part of it, you will be left with a bit.
Even if you remove another part, the bit still remains.
Remove one more and it still remains.

What is it?