What is the word or phrase?

In the below-given picture of a pretty girl, there is something wrong. Can you find out what it is?

What goes up but never comes down?

How could a baby fall out of a twenty-story building onto the ground and live?

When Jack was six years old he hammered a nail into his favourite tree to mark his height. Ten years later at age sixteen, Jack returned to see how much higher the nail was. If the tree grew by five centimetres each year, how much higher would the nail be?

Which tank will fill first?

Can you solve below mathematical equation?

2^1234 - 2^1233

John is the son of Jacob.
So,
Jacob is the_____of John's father?

In the picture that is attached with this question, you can find a square which comprises of four little squares inside it. Consider this square to be made with matchsticks. You have to remove two matchsticks such that only two squares remain instead of five.How will you do it ?

12345 a famous South Indian actor
567 is a path in jumbled form
8 & 10 are same letters
9 is one among the first six alphabets.
WHO AM I?