1. Let set $A = \{ x \mid - 1 < x < 2 \}$ and set $B = \{ x \mid 1 < x < 3 \}$. Then $A \cup B =$ (A) $\{ x \mid - 1 < x < 3 \}$ (B) $\{ x \mid - 1 < x < 1 \}$ (C) $\{ x \mid 1 < x < 2 \} \{ x \mid 2 < x < 3 \}$ (D)
1. Let set $A = \{ x \mid - 1 < x < 2 \}$ and set $B = \{ x \mid 1 < x < 3 \}$. Then $A \cup B =$\\
(A) $\{ x \mid - 1 < x < 3 \}$\\
(B) $\{ x \mid - 1 < x < 1 \}$\\
(C) $\{ x \mid 1 < x < 2 \} \{ x \mid 2 < x < 3 \}$\\
(D)