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.
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Question: Question: Find the fourth proportion to 2,4,6

 Option A: 18

 Option B: 12

 Option C: 9

 Option D: 6

 Option E: 8

Answer: Option B


Question: Question: Find the equation of a line which passes through A(4, -1) and is parallel to x axis.

 Option A: y=-2

 Option B: y=3

 Option C: y=2

 Option D: y=-1

 Option E: y=0

Answer: Option D


Question: Question: The difference between C.I. and S.I. on an amount of $20,000 for 2 years is $72. What is the rate of interest per annum?

 Option A: 5%

 Option B: 6%

 Option C: 7%

 Option D: 8%

 Option E: 9%

Answer:
Option B