If the molar density of a binary mixture is given by the empirical expression

Did the universe cool off or get hotter as it expanded after the 'big bang"?

Two technicians are discussing how to test a car's exhaust by holding a small piece of paper within an inch of the tailpipe mouth. technician a says that if the paper is vibrating due to a "puffing" output from the tailpipe, this signals a smoothly running engine. technician b says that if the paper is being drawn toward the tailpipe, this could indicate burned exhaust valves. who is correct? a. technician b b. both technicians a and b c. technician a d. neither technicians a or b

In 1919, the temperance movement finally succeeded. they secured ratification of a constitutional amendment (the that banned alcoholic beverages. prohibition began with the 1920 passage of the which enforced the amendment.