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: A rectangular plot measuring 90 metres by 50 metres is to be enclosed by wire fencing. If the poles of the fence are kept 10 metres apart, how many poles will be needed ?

 Option A: 28

 Option B: 56

 Option C: 57

 Option D: 58

 Option E: None of these

A: Option A
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Q: Question: If the average (arithmetic mean) of 18 consecutive odd integers is 414, then the least of these integers is

 Option A: a

 Option B: b

 Option C: c

 Option D: d

 Option E: e

A: Option A
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Q: Question: The inner circumference of a circle race track 18 m wide is 880 m. Find the radius of the outer circle.

 Option A: 120m

 Option B: 145m

 Option C: 130m

 Option D: 140m

 Option E: 122m

A:
Option D
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