I am white when I am dirty, and black when I am clean. What am I?

I know a nine-letter word having only one vowel.
Do you ?

During which month do people sleep the least?

John was going on a jungle trip. He asked his wife to pack something to eat, something to drink and something to burn if he feels cold in the jungle. When John opens the backpack he found just one thing in the bag. What was it?

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?

Can you find the missing piece of the Porsche?

A wooden log balances equally on the scales when weighed with three-quarters of a pound and three-quarters of a wooden log.

Can you calculate the weight of the entire wooden log?

If eleven plus two equals one, what does nine plus five equal?

A man started to town with a fox, a goose, and a sack of corn. He came to a stream which he had to cross in a tiny boat. He could only take one across at a time. He could not leave the fox alone with the goose or the goose alone with the corn. How did he get them all safely over the stream?

I have an eye but still cannot see.

Who am I?