You are given a math word problem and you are supposed to make use of mathematical concepts like probability, combinatorics, linear equations, sequences/series, or simple operators like addition, subtraction, division, or multiplication to answer the given question. Choose the best option from the 5 given options and report that option.

Q: Question: The compound ratio of 1:3, 3:2 and 4:5?

 Option A: 1:9

 Option B: 1:7

 Option C: 1:2

 Option D: 2:5

 Option E: 1:4

A: Option D
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Q: Question: There are 36 students in a certain geometry class. If one third of the students are boys and one fourth of the boys are under six feet tall, how many boys in the class are under six feet tall?

 Option A: 3

 Option B: 12

 Option C: 18

 Option D: 24

 Option E: 27

A: Option A
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Q: Question: A manufacturer of a certain product can expect that between 0.3 percent and 0.5 percent of the units manufactured will be defective. If the retail price is $2,500 per unit and the manufacturer offers a full refund for defective units, how much money can the manufacturer expect to need to cover the refunds on 20,000 units?

 Option A: Between $15,000 and $25,000

 Option B: Between $30,000 and $50,000

 Option C: Between $60,000 and $100,000

 Option D: Between $150,000 and $250,000

 Option E: Between $300,000 and $500,000

A:
Option D
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