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: Rob traveled a distance of 30 km, covering the first 10 km in x minutes, the next 10 km in y minutes and the last 10 km in z minutes. If he totally took 3y minutes to cover the whole distance, then which of the following cannot be true? Assume x , y and z are different.

 Option A: z=3x

 Option B: x=3z

 Option C: y=2x

 Option D: x=2y

 Option E: y=3x

A: Option D
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Q: Question: if (HE)^H=SHE,where the alphabets takes the values from (0-9) & all the alphabets are single digit then find the value of (S+H+E)

 Option A: 10

 Option B: 13

 Option C: 5

 Option D: 19

 Option E: data in sufficient

A: Option B
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Q: Question: A boatman goes 3 km against the current of the stream in 3 hour and goes 1 km along the current in 30 minutes. How long will it take to go 3 km in stationary water?

 Option A: 5 hours

 Option B: 4 hours

 Option C: 3 hours

 Option D: 2 hours

 Option E: 1 hours

A:
Option D
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