The chemical acidity of a solution is measured in units of pH: , where  is the hydrogen ion concentration in the solution. If a sample of rain has a pH of 3.4, how many times higher is its 

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A.
B.
C. 7
D.
E.

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Answer: A

Mathematics

Use the given transformation to evaluate the integral.     Rwhere R is the parallelepiped bounded by the planes   

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A.
B.
C.
D.

Provide an appropriate response.At or before a real estate closing, which of the following may be included:

A. mortgage closing costs B. good faith estimate C. points D. all of these may be required before or during closing

Provide an appropriate response.Which one of the following is a description of the graph of the solution set for the system below?x2 + y2 ? 364x2 + 9y2 ? 36

A. The area inside the circle (defined by the first equation) and outside the ellipse (defined by the second equation), including both borders. B. The area inside the ellipse (defined by the second equation) and outside the circle (defined by the first equation), including both borders. C. The area inside the ellipse (defined by the second equation), including the border. D. None of these

Solve the equation. = 

A. , 
B. No solution
C. , - 
D. - , - 2