Find the minimized Boolean expression for the functions defined by each of the following truth tables:

b) \begin{tabular}{|l|l|l|l|l|} \hlinew & x & y & z & F \\ \hline 0 & 0 & 0 & 0 & 0 \\ \hline 0 & 0 & 0 & 1 & 1 \\ \hline 0 & 0 & 1 & 0 & 0 \\ \hline 0 & 0 & 1 & 1 & 0 \\ \hline 0 & 1 & 0 & 0 & x \\ \hline 0 & 1 & 0 & 1 & 0 \\ \hline 0 & 1 & 1 & 0 & x \\ \hline 0 & 1 & 1 & 0 \\ \hline 1 & 0 & 0 & 1 & 1 \\ \hline 1 & 0 & 0 & x & x \\ \hline 1 & 0 & 1 & 1 & x \\ \hline 1 & 0 & 1 & 0 & 1 \\ \hline 1 & 1 & 0 & 1 & x \\ \hline 1 & 1 & 0 & 0 & x \\ \hline 1 & 1 & 1 & 1 & x \\ \hline 1 & 1 & 1 & 1 & \\ \hline \end{tabular}