Why do we preferably have round manhole covers and not square ones?

Today is John's birthday.
A year ago, John had five candles and he lit all the candles except the one at the last.
Now he is going to light all the candles.

How old is John Today?

(He is not five today.....)

Two batsman each on 94 runs. Seven runs needed to win in last 3 balls. Both make 100*. How?

Look at the picture and find out which square is not linked with any of the other squares.

What goes up but never comes down?

What has 13 hearts but no other organs?

As shown in the picture below, we can see a boy hanging on the tree branch to save his life. There are various ways in which he can die like1. A snake hanging toward the right waiting to bite the boy.2. A roaring Lion near the tree.3. Two crocodiles are ready to attack if the boy reaches near water. The tree is chopped to some extent, so can fall as if he moves a lot. Can you give this boy an escape plan?

On my way to St. Ives I saw a man with 7 wives. Each wife had 7 sacks. Each sack had 7 cats. Each cat had 7 kittens. Kittens, cats, sacks, wives. How many were going to St. Ives?

By including only four matchsticks in below picture, you have to make "Four Triangles And Two Squares"

Cristina was born in 1888. She just had her 30th birthday today how did that happen?