Rita is a self$-$employed taxpayer who turns $39$ years old at the end of the year $(2023).$ In $2023,$ her net Schedule C income was $$300,000.$ This was her only source of income. This year, Rita is considering setting up a retirement plan.

What is the maximum amount Rita may contribute to the self$-$employed plan in each of the following situations?

a$.$ She sets up a SEP IRA?