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

What shoe company does this rebus represent?

They came out at night, without being called.
They lost at day, without being stolen.
Who are they?

Can you find the key in the picture below?

How can you tell a raw egg from a hard-boiled egg?

When I got four, I have it none.
When I got two, I have it some.
When I got none, I have it all.

What is it?

Wednesday, Steve and Pam go to a restaurant to eat lunch. After eating lunch, they pay the bill. But Steve and Pam do not pay the bill. So…who does?

After teaching his class all about Roman numerals (X = 10, IX=9 and so on) the teacher asked his class to draw a single continuous line and turn IX into 6. The teacher's only stipulation was that the pen could not be lifted from the paper until the line was complete.

Your last good ping-pong ball fell into a narrow metal pipe embedded one foot deep in concrete.
How can you get it out undamaged, if all the tools you have are your tennis paddle, shoe laces, and plastic water bottle, which does not fit into the pipe?

Can you find out the missing number in the grid?