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: an 80 - liter solution of cool - drink is made from 10 % jasmine water. if 5 liters of jasmine and 15 liters of water were added to the solution, what percent of the solution is jasmine ?
Options: a. 11 %, b. 13 %, c. 15 %, d. 17 %, e. 19 %

A: b
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Q: Problem: what is the value of ( 2 ) ^ - 3 ?
Options: a. 1 / 6, b. 1 / 5, c. 1 / 8, d. 1 / 9, e. 1 / 7

A: c
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Q: Problem: 40 % of a number is added to 60, the result is the same number. find the number ?
Options: a. 300, b. 288, c. 270, d. 100, e. 281

A:
d
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