What does this simple rebus mean?

At a party, there are five people and a whole round cake lying at the centre of the table. Only four people will make a cut and take their piece and the last one will get the remaining piece on the table. How can they make sure that everyone gets a 1/5th of the piece?

Find the smallest sentence with all the English alphabet.

What occurs twice in a week, once in a year but never in a day?

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

There is a square piece of paper with a hole that is denoted by the circle on the top right side in the given picture. You have to cut the paper in a manner that it forms two and only two separate pieces of paper and then rearrange the pieces in a manner that the holes come in the centre of the paper.

What kind of band never plays music?

As easy as you can get into me, it is as hard to get out of me.

Do you know what I am?

Akbar called Birbal and asked him to draw a line on the floor. He asked Birbal to make that line smaller without erasing it. Birbal smiled and did it before Akbar could blink his eyes.

How did he managed to do it?

I have an eye but still cannot see.

Who am I?