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: lloyd normally works 7.5 hours per day and earns $ 3.50 per hour. for each hour he works in excess of 7.5 hours on a given day, he is paid 1.5 times his regular rate. if lloyd works 10.5 hours on a given day, how much does he earn for that day ?
Options: a. $ 33.75, b. $ 42.00, c. $ 51.75, d. $ 54.00, e. $ 70.00
[A]: b


[Q]: Problem: the average weight of a group of persons increased from 48 kg to 51 kg, when two persons weighing 78 kg and 93 kg join the group. find the initial number of members in the group ?
Options: a. 87, b. 67, c. 23, d. 75, e. 25
[A]: c


[Q]: Problem: how much water should be added to 13 liters of a 20 % - solution of alcohol to reduce the concentration of alcohol in the solution by 75 % ?
Options: a. 25 liters, b. 27 liters, c. 30 liters, d. 32 liters, e. 35 liters
[A]:
b