The program su enables a UNIX user to access another user’s account. Unless the first user is the superuser, su requires that the password of the second user be given. A (possibly apocryphal) version of su would ask for the user’s password and, if it could not determine if the password was correct because the password file could not be opened, immediately grant superuser access so that the user could fix the problem. Discuss which of the design principles this approach meets, and which ones it violates. solution online stackoverflow

Jaina and tomas are being considered as new tenants in an apartment. the landlord looks at their creditworthiness because he wants to be sure his new tenant pays the rent on time and in full. the table below summarizes the information that was on their applications. application information questions jaina tomas how many years have you had your job? 5 2 what is your monthly salary? $1,850 $2,500 how many credit cards do you have? 4 1 how much debt do you have? $13,000 $7,000 how many times were you late with payments on credit cards in the past year? 5 1 who will the landlord decide to be more creditworthy and why? tomas because the ratio of his debt to income is less. jaina because she has had her job longer, which makes her look more stable. jaina because she has more credit cards available to her. tomas because he makes more money per month.