What is always in front of you but can’t be seen?

Teacher ask the student

'Why are you standing on that chair in music class ?'.

what did student replied ?

What will you call your mother's brother's brother-in-law?

Can you find out what is missing?

1 3 5
2 4 ?

Hint: It's not six. Think out of the box.

What is full of holes but still holds water?

What am I?

Paul's height is six feet, he's an assistant at a butcher's shop and wears size 9 shoes. What does he weigh?

In a concert, Christina is performing a dance show with her group.
At 10:00, she and her crew were dancing in an absolutely straight line. At that time Christina was standing in 4th position from both the front and back end of the row.

What was the size of her crew?

What does below Rebus mean ?

esgg sgeg gegs gsge

John Went to the nearby store in a Mall to buy something for her home. Below is the conversation between the two:

John: How much for the one?
Shopkeeper: It is $2
John: How much for the Eleven?
Shopkeeper: It is $4
John: How much for the Hundred?
Shopkeeper: It is $6.

What is John buying?