code class$=$"asciimath"$>$B and $C$ are sets of real numbers defined as follows. $B=\{z|z<3\}C=\{z|z7\}$ Write $BC$ and $BC$ using interval notation. If the set is empty, write $\frac{O}{?}.BC=BC=,-$ Back Reload P Save Pag Print PagB and $C$ are sets of real numbers defined as follows. $B=\{z|z<3\}C=\{z|z7\}$ Write $BC$ and