A scientist needs 60 liters of a 40% solution of alcohol. He has a 30% solution and a 60% solution available. How many liters of the 30% solution and how many liters of the 60% solution should he mix to make the 40% solution?

The depreciation per unit for a company

Which approach to the theory-and-research cycle does the following sequence reflect: (1) specific observations suggest generalizations, (2) generalizations produce a tentative theory, (3) the theory is tested through the formation of hypotheses, and (4) hypotheses may provide suggestions for additional observations?

If y varies directly as x2 and y=6 when x=6, find the constant of variation.