useless trivia: What Word Means: Soots?

Questions

who was america's first public enemy no 1?

a person will die in approximately 10 days without what?

according to german researchers, the risk of heart attack is highest on what day of the week?

after spending hours working at a computer display, what colour will a blank piece of white paper probably appear to be?

a banana is not a fruit, but a ______?