You are given a mathematical question described with an open-ended vocabulary. Questions in this task involve real-world situations, describing a mathematical problem. You are also given 4 or 5 answer options (associated with "A", "B", "C", "D", "E"). Do not generate anything else apart from one of the following characters: 'A', 'B, 'C', 'D', 'E'. LaTeX mathematical format (the standard way to express mathematical expressions in the typesetting software known as LaTeX) is used to express equations. Each question is solvable with high school math knowledge. Give only one answer for each question.

Q: A survey of all the students who attend Central Valley High School showed that there was an average (arithmetic mean) of 33.6 students per class room and and average of 22.4 electronic devices brought to class by students per classroom. If 4,200 students attend Central Valley High School, which of the following is the best estimate of the total number of electronic devices in the classrooms of Central Valley?
(A)1,680 (B)2,520 (C)2,800 (D)4,075 (E)6,300

A: C
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Q: If pencils cost $0.50 each and notebooks cost $3 each, which of the following represents the cost, in dollars, of p pencils and n notebooks?
(A)\(2pn\) (B)\(3.5pn\) (C)\(3.5(n + p)\) (D)\(3n + 0.50p\) (E)\(2(n + 0.50p)\)

A: D
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Q: Jo spends 25 percent of her monthly income on food, 30 percent on rent, 20 percent on insurance, and 10 percent on entertainment and miscellaneous expenses. Of her remaining income, she gives half to charity and saves the rest. If Jo saves 75 dollars every month, what is her total monthly income?
(A)\$1,000 (B)\$1,500 (C)\$1,600 (D)\$2,500 (E)\$5,000

A:
A
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