A solution had an original concentration of 20%. It was then diluted and the final concentration was 15%. Determine the dilution performed.

A group leader who tries to control group members by ordering them around is known as what kind of a leader?

A. democratic B. laissez-faire C. autocratic D. trait oriented

A lens with a single focal length (a 25mm lens, a 50mm lens, a 150mm lens, etc.) is called a:

A. crane lens B. zoom lens C. scope lens D. prime lens