Given that an operating system has a degree of multiprogramming of $30,$ answer the following.

State whether or not the following state is possible: $1$ process is running, $10$ processes are in the disk$-1$ queue, $5$ processes are waiting in disk$-2$ queue, $10$ processes are in the ready queue, and $15$ processes have completed execution. Justify.

If a currently running process P$0$ executes a return statement in a function in a language such as C$++$ or Java, what happens $($if any$)$ to its state after the execution?