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(3) Let P(x, y) be "x and y are related", let U(x) be "x is an uncle", and let A(x) be "x is an aunt". Translate the following into formulas, where

the domain for the variables is the collection of all people. (a) Everyone is related to a person who is both an aunt and an uncle. (b) There is exactly one uncle. (c) Everyone is related to him/her/themself as well as to two (different) uncles (note: I did NOT say is related to EXACTLY two uncles, so be careful). (d) John is related to Mary and to Martha but to no one else. (e) The collection of people that John is related to is exactly the same as the collection of people that are related to either Peter or to Mary.

Fig: 1