Why is a river so rich ?

I had an infinite supply of water and 5 litres and 3 litres jars.

How would you measure exactly 4 litres in the least number of steps?

Take number 1000 and then add 20 to it.
Now add 1000 one more time.
Now add 30.
Now add 1000 one more time.
Now add 40.
Now add 1000 one more time.
Now add 10.

What is the total?

How many triangles can you count in the figure given?

Why is 6 afraid of 7?

Can you write down eight eights so that they add up to one thousand?

What is 3/7 chicken, 2/3 cat and 2/4 goat?

I inserted a coin in a bottle and closed its mouth with the help of a cork. Now, I was able to take the coin out from the bottle without taking out the cork or breaking the bottle. Can you tell me how I did it?

Two in a corner, one in a room, zero in a house, but one in a shelter. What is it?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?