Rhea Xu is a self$-$employed professional singer$.$ She resides in a rented apartment and uses one room exclusively as a business office. This room includes $390$ of the $2,600$ square feet of living space in the apartment. Ms$.$ Xu performs in recording studios and concert halls, but she conducts all of the administrative duties with respect to the business in her home office. This year, Ms$.$ Xu$$s apartment rent was $$59,000.$ She paid $$6,300$ to a housekeeping service that cleaned the entire apartment once a week and $$3,100$ for renter$$s insurance on the apartment furnishings.

Required:

a$.$ Compute Ms$.$ Xu$$s home office deduction assuming that her net profit before the deduction was $$410,000.$

b$.$ Compute Ms$.$ Xu$$s home office deduction assuming that her net profit before the deduction was $$5,100.$