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 fish can go upstream at 35 kmph and downstream at 55 kmph, and then find the speed of the fish in still water?

 Option A: 45

 Option B: 55

 Option C: 35

 Option D: 65

 Option E: 70
[A]: Option A


[Q]: Question: Find the number of ways of arranging the letters of the word "MATERIAL" such that all the vowels in the word are to come together?

 Option A: 1887 ways

 Option B: 1440 ways

 Option C: 1657 ways

 Option D: 1652 ways

 Option E: 6745 ways
[A]: Option B


[Q]: Question: A's salary is 40% of B's salary which is 25% of C's salary. What percentage of C's salary is A's salary ?

 Option A: 10

 Option B: 20

 Option C: 30

 Option D: 40

 Option E: 50
[A]:
Option A