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 reduction of 20% in the price of salt enables a lady to obtain 10kgs more for Rs.100, find the original price per kg?

 Option A: Rs.3.2

 Option B: Rs.2.9

 Option C: Rs.2.5

 Option D: Rs.5.2

 Option E: Rs.2.1

A: Option C
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Q: Question: Donald plans to invest x dollars in a savings account that pays interest at an annual rate of 8% compounded quarterly. Approximately what amount is the minimum that Donald will need to invest to earn over $100 in interest within 6 months?

 Option A: 1500

 Option B: 1750

 Option C: 2000

 Option D: 2500

 Option E: 3000

A: Option D
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Q: Question: A train 100 meters long completely crosses a 300 meters long bridge in 45 seconds. What is the speed of the train is?

 Option A: 32

 Option B: 82

 Option C: 83

 Option D: 89

 Option E: 73

A:
Option A
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