How can a man go eight days without sleep?

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

Can you make a fire with just a single stick?

Can you find out the remainder when 3^300 is divided by 5?

My grandson is about as many days as my son in weeks, and my grandson is as many months as I am in years. My grandson, my son and I together are 120 years. Can you tell me my age in years ?

I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

Can you count the number of seconds in a year?

Clue: You need to bother about calculation.

Can you solve the equation by finding the value of
A) Horse
B) Cowboy boot
C) Horseshoe

In the Picture?

What common phrase is represented by the below lines

Easy going:
Weak, 'I'm going.'
Tough, 'I'm staying.'

Medium going:
Weak, 'I'm going.'
Tough, 'I'm staying.'

Tough going:
Weak, 'I can't do it, I'm staying!'
Tough, 'Let's get going.'

In a classic wine shop, the list of three most popular wines are:
- The cost of 1 French wine bottle: 500$
- The cost of 1 German wine bottle: 100$
- The cost of 20 Dutch wine bottles: 100$

John entered the wine shop and he needs to buy
- All three types of wine bottles.
- Needs to buy Dutch wine bottles in multiples of 20.
- Need to buy 100 wine bottles in total.

John has only 10000$. How many wine bottles of each type, John must buy?