Sets A, B and C are subsets of the universal set U. these sets are defined as follows
Sets \( A, B \), and \( C \) are subsets of the universal set \( U \). These sets are defined as follows. \[ \begin{array}{l} U=\{f, g, h, p, q, r, x, y, z\} \\ A=\{f, r, x, y, z\} \\ B=\{f, h, p, x, z\} \\ C=\{p, q, r, x\} \end{array} \] Find \( A \cup(B \cap C)^{\prime} \). Write your answer in roster form or as \( \varnothing \).