A$.(10)$ Let $D$ be a language over $\{a,b\}$ where contains an even number of a$\text{'}$s and an odd number of $b\text{'}$s$,$ and does not contain the

substring $ab.$ Give a DFA with five states that recognizes $D.$

B$.(15)$ In certain programming languages, comments appear between delimiters such as $/$# and #$/.$ Let $C$ be the language of all valid delimited

comment strings. A member of $C$ must begin with $/$# and end with #$/$ but have no intervening #$/.$ For simplicity, assume that the alphabet for $C$

is $=\{a,b\frac{,}{,}$#$\}.$ Give a DFA that recognizes $C.$