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.

[EX Q]: Problem: on a certain day, orangeade was made by mixing a certain amount of orange juice with an equal amount of water. on the next day, orangeade was made by mixing the same amount of orange juice with twice the amount of water. on both days, all the orangeade that was made was sold. if the revenue from selling the orangeade was the same for both days and if the orangeade was sold at $ 0.30 per glass on the first day, what was the price per glass on the second day ?
Options: a. $ 0.15, b. $ 0.20, c. $ 0.30, d. $ 0.40, e. $ 0.45
[EX A]: b

[EX Q]: Problem: if x + y = 260, x - y = 200, for integers of x and y, y = ?
Options: a. 200, b. 230, c. 50, d. 115, e. 150
[EX A]: b

[EX Q]: Problem: angelo and isabella are both salespersons. in any given week, angelo makes $ 560 in base salary plus 8 percent of the portion of his sales above $ 1,000 for that week. isabella makes 10 percent of her total sales for any given week. for what amount of weekly sales would angelo and isabella earn the same amount of money ?
Options: a. 23,500, b. 24,000, c. 25,500, d. 26,500, e. 27,500
[EX A]:
b