Consider a function, called ADD$0,$ which converts a given input language to a new output language such that for each string $w$ in the input language, there is a corresponding one in the output language that starts with the same characters as $w$ but has an extra $0$ at the end. Formally:

ADD$0(L)=\{w0|$ where $wis$ a string inL$\}$

If the alphabet for a language $L$ is $,$ then the alphabet for ADD$0(L)$ is $0.$

Consider the following language:

is a three digit number starting with $4$