Answer
$ a) ∀xA(x). $
$b) S(file system, locked)⇒∀xA(x,system mailbox). $
$c)S(firewall, diagnostic)⇒S(proxy server, diagnostic). $
$d) (T(100)∧¬T(500)∧¬M(proxy server, diagnostic))⇒∃x S(x, normal).$
Work Step by Step
There are many ways to write these, depending on what we use for predicates.$
$a) Let "A(x)"be "User has access to an electronic mailbox." Then we have ∀xA(x). $
$b) Let A(x, y) be "Group member z can access resource y," and let S(x,y) be "System is in state y." Then we have S(file system, locked)⇒∀xA(x,system mailbox). $
$c) Let S(x,y) be "System is in state y. Recalling that only if indicates a necessary condition, we have S(firewall, diagnostic)⇒S(proxy server, diagnostic). $
$d) Let T(x) be "The throughput is at least x kbps," where the domain of discourse is positive numbers, Int M(x,y) be "Resource x is in mode y," and let. S(x,y) be "Router x is in state y." Then we have (T(100)∧¬T(500)∧¬M(proxy server, diagnostic))⇒∃x S(x, normal).
