Access Report Header And Sorting

I am working on a access report for financial analysis.I created a form with a drop down list to select cost center from tables, so the report will only show the data from the selected cost center. My questions are:

1. I want the chosen cost center automatically shown at the Header of the report, as selected from the form;

2. The data was grouped in a particular sequence, such as: Revenue, Compensation, MM&S and Other Expense, not simply ascending or descending

3. There are some category data I do not want to show, for example, other expense, how can I hide it?