What does this rebus riddle means ?

When it's bad luck to meet a black cat?

How do you go from 98 to 720 using just one letter?

A woman is sitting in her hotel room and hears a knock at the door. She opens the door to see a man whom she’s never met before. He says, “I’m sorry, I have made a mistake, I thought this was my room.” He then goes down the corridor and into the elevator. The woman goes back into her room and calls security. What made the woman so suspicious of the man?

A wealthy man lives alone in a small cottage. Being partially handicapped he had everything delivered to his cottage. The mailman was delivering a letter one Thursday when he noticed that the front door was ajar. Through the opening he could see the man's body lying in a pool of dried blood. When a police officer arrived he surveyed the scene. On the porch were two bottles of warm milk, Monday's newspaper, a catalog, flyers, and unopened mail. The police officer suspects it was foul play. Who does he suspect and why?

Solve below popular number sequence
314 159 265 358 979 323 846 ?

The dirtier I get, the whiter I look. Who am I?

I am never scared but became petrified and can’t live in a house but would die to make one. What am I?

A Man gave one of his sons 10 cents and another son was given 15 cents. What time is it?
Hint: Figure out the relation between time and number, is not so easy..:)

You see a boat filled with people, yet there isn’t a single person on board. How is that possible?