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: What is the area of an equilateral triangle whose one side length is 80?

 Option A: 800√3

 Option B: 1000√3

 Option C: 1200√3

 Option D: 1400√3

 Option E: 1600√3

A: Option E
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Q: Question: Read the following three equations:
5 ~ 4 ~ 3 ~ 9 = 4215
6 ~ 9 ~ 2 ~ 6 = 3816
4 ~ 7 ~ 3 ~ 3 = 1122
Now based on the rule that has been used, solve the following equation:
4 ~ 2 ~ 7 ~ 4 = ____

 Option A: 1416

 Option B: 2910

 Option C: 2940

 Option D: 3749

 Option E: 4470

A: Option A
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Q: Question: A person can row at 9 kmph and still water. He takes 3 1/2 hours to row from A to B and back. What is the distance between A and B if the speed of the stream is 1 kmph?

 Option A: 16 km

 Option B: 87 km

 Option C: 89 km

 Option D: 67 km

 Option E: 20 km

A:
Option A
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