Can you convert the number zero(0) into a positive number using just one mathematical operator ?

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

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

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

Can you find the least possible number such that

If the number is divided by 3, it gives the remainder of 1;
If the number is divided by 4, it gives the remainder of 2;
If the number is divided by 5, it gives the remainder of 3;
If the number is divided by 6, it gives the remainder of 4.

Make eight squares by moving only two matchsticks.
Note- Square can be of different sizes.

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?

You are given 2 eggs.
You have access to a 100-storey building.
Eggs can be very hard or very fragile means it may break if dropped from the first floor or may not even break if dropped from 100th floor, Both eggs are identical.
You need to figure out the highest floor of a 100-storey building an egg can be dropped without breaking.
Now the question is how many drops you need to make. You are allowed to break 2 eggs in the process

You knock a Table over in the library, and suddenly 20 eyes are looking at you.

I throw two dice simultaneously.

What is the probability of getting a sum as 9 of the two numbers shown?