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: how many positive even integers less than 100 contain digits 5 or 7 ?
Options: a. 10, b. 17, c. 18, d. 19, e. 20
a

Problem: the average score of a cricketer in 2 matches is 30 and in other 3 matches is 40. then find the average score in all the 5 matches ?
Options: a. 25, b. 27, c. 30, d. 35, e. 36
e

Problem: the megatek corporation is displaying its distribution of employees by department in a circle graph. the size of each sector of the graph representing a department is proportional to the percentage of total employees in that department. if the section of the circle graph representing the manufacturing department takes up 216 of the circle, what percentage of megatek employees are in manufacturing ?
Options: a. 20 %, b. 25 %, c. 30 %, d. 35 %, e. 60 %
e