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.

Problem: a ( 3, w ^ 3 ) is the ( x, y ) coordinate of point located on the parabola y = x ^ 2 - 1. what is the value of w ?
Options: a. 2., b. 4., c. 5., d. 6., e. 9.
a

Problem: the overall age of x and y is 19 year greater than the overall age of y and z. z is how many decades younger that x ?
Options: a. 11, b. 15, c. 12, d. 19, e. 20
d

Problem: a slot machine in a las vegas casino has an average profit of $ 600 for each 8 - hour shift for the 5 days sunday through thursday, inclusive. if the average per - shift profit on friday and saturday is 25 % greater than on the other days of the week and the slot machine is in operation every hour of every day, what is the total weekly profit that the casino makes from the slot machine ?
Options: a. a - 4500, b. b - 9000, c. c - 13500, d. d - 15500, e. e - 27000

c