I need to ask a question its for the guys... please?

Acylinder is filled with 2.00 moles of nitrogen, 3.00 moles of argon and 5.00 moles of helium. if the gas mixture is at stp, what is the partial pressure of the argon

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.

List four observations that indicate that a chemical reaction may be taking place