Riddles about fireplaces

Two workmen were repairing a roof. Suddenly, they both fell down the chimney and found themselves in the large fireplace. One man`s face was smeared with soot and one wasn`t. The one with the clean face washed his and the dirty man did not and went back to work. Why?

What is black when you buy it, red when you use it, and gray when you throw it away?

If you had one match and entered a room in which there were a kerosene lamp, an oil burner, and a wood burning stove, which would you light first?