What number should come in place of the question mark below?

Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

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

When did John make this statement?

John and Jacob are twin brothers. One of them is a liar whereas the other one is a truth-teller.

I called their home number and one of them picked up.
I asked. 'Does John lie?' The person replied with a yes.

Whom did I talk with, John or Jacob?

I can be cracked, made, told, and played. What am I?

What does this mathematical rebus means ?

Irene killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Can you find the dog hidden in a group of pandas?

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?

You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?