Which set of ordered pairs represents a function?

\{(-4, -2), (4, 1), (4, -7), (-2, 3)\}{(−4,−,,−−2,3)}
\{(-9, -2), (5, -6), (-4, 3), (5, 2)\}{(−9,−,−−4,,2)}
\{(-8, 0), (-4, -9), (-6, -1), (2, -1)\}{(−8,−4,−−6,−,−1)}
\{(5, -7), (1, 4), (7, -3), (1, -8)\}{(5,−,,−,−8)}

Perry observes the opposite parallel walls of a room in how many lines do the plains containing the walls intersect

Which is a logical conclusion based on the given information? a. figure abcd is a rhombus by the definition of a rhombus. b. segment ac is congruent to segment dc by cpctc. c. angle acb is congruent to angle adc by the angle-side-angle theorem. d. triangle acd is congruent to triangle cab by the hypotenuse-leg theorem.

Me i’m stuck on all these questions besides the two bottom ones