Can’t figure out the numbers

Suppose that alexi and tony can sell all their street tacos for $2 each and all their cuban sandwiches for $7.25 each. if each of them worked 20 hours per week, how should they split their time between the production of street tacos and cuban sandwiches? what is their maximum joint revenue?

Perry is a freshman, he estimates that the cost of tuition, books, room and board, transportation, and other incidentals will be $30000 this year. he expects these costs to rise about $1500 each year while he is in college. if it will take him 5 years to earn his bs, what is the present cost of his degree at an interest rate of 6%? if he earns and extra $10000 annually for 40 years, what is the present worth of his degree.?

Problem 3: access control pokeygram, a cutting-edge new email start-up, is setting up building access for its employees. there are two types of employees: managers and engineers, and there are three departments: security, networking, and human resoures. each employee works in a single department, and each department is housed on a different floor. managers are allowed access to any floor, while engineers are allowed access only to their own floor. there are three badge-operated elevators, each going up to only one distinct floor. every employee has one badge. pokeygram wants to use the best possible access control method in order to minimize delay for the elevators (a) access control matrix, 1. which of the following would you recommend that pokeygram use: (b) access control lists, or (c) capabilities? make sure to justify your answer. 2. what, if any, would be the benefits (and/or disadvantages) of using rbac (role-based access control) in this situation? keep your solution for this problem limited to 10-12 lines of text.