Given a math problem with context and a question and 5 answer choices, the task is to provide the correct answer choice based on the problem. You must choose one of the given answer choices by letter: a, b, c, d, or e; anything else is invalid.

Q: Problem: a / ( b / c. in the expression above, a, b, and c are different numbers and each is one of the numbers 2, 3, or 6. what is the largest possible value of the expression ?
Options: a. 2 / 18, b. 6 / 3, c. 30 / 2, d. 18 / 2, e. 6 / 18

A: d
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Q: Problem: in one hour, a boat goes 19 km / hr along the stream and 9 km / hr against the stream. the speed of the boat in still water ( in km / hr ) is :
Options: a. 12 kmph, b. 13 kmph, c. 14 kmph, d. 15 kmph, e. 16 kmph

A: c
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Q: Problem: what will be the cost of gardening 1 meter boundary around a rectangular plot having perimeter of 340 meters at the rate of rs. 10 per square meter ?
Options: ['a. rs. 3430', 'b. rs. 3440', 'c. rs. 3450', 'd. rs. 3460', 'e. rs. 3490']

A:
b
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