A homeowner in a sunny climate has the opportunity to install a solar water heater in his home for a cost of $3,979. After installation the solar water heater will produce a small amount of hot water every day, forever, and will require no maintenance. How much must the homeowner save on water heating costs every year if this is to be a sound investment

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.