In which direction should the missing arrow point?

I have holes on the top and bottom. I have holes on my left and on my right. And I have holes in the middle, yet I still hold water. What am I?

Can you count the number of squares in the figure below?

Teacher ask the student

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

what did student replied ?

What have one eye but still cannot see?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?

One night, a woman receives a call from the police. They tell her that her husband was murdered and that she should come to the crime scene as soon as possible. The woman drops the phone, shocked, and drives 20 minutes to the crime scene. As soon as she reaches the crime scene, the police arrest her and she is convicted of murder. How do the police know she committed the crime?

A sea diver is a real show-off. He showed everyone that he can hold his breath underwater for 15 minutes.

I went to the diver and told him that I can be underwater for double the time i.e 30 minutes.
He responded that he will give me 100$ if I would be able to do it. I won 100$.

What did I do?

What does the following BrainBat signifies?

ABCDEFGHIJKLMNOPQRSTUVWYZ

QQQQQQQQQQQQQQQQQQQQQQQQQ.

John said, "If yesterday was tomorrow, today would be Friday."

When did John make this statement?