Mark each statement True or False. Justify each answer. (a) Axioms A1 to A5, M1 to M5, DL, and O1 to O4 describe an algebraic system known as an ordered field. (b) If x, y ∈ R and x 0, then x (c) If...

Mark each statement True or False. Justify each answer.

(a) Axioms A1 to A5, M1 to M5, DL, and O1 to O4 describe an algebraic system known as an ordered field.

(b) If x, y ∈ R and x <> 0, then x

(c) If x, y ∈ R, then | x + y | = | x | + | y |.