(1) determining, assessing, and collecting any sales and use tax imposed pursuant to this chapter;
(2) representing each county, city, and town's interest in any administrative proceeding involving the state or local option sales and use tax;
(3) adjudicating any administrative proceedings involving the state or local option sales and use tax;
(4) waiving, reducing, or compromising any penalty and interest imposed in connection with any determination of state or local option sales or use tax; and
(5) prescribing forms and rules to conform with this chapter for the making of returns and for the ascertainment, assessment, and collection of the taxes imposed under this chapter.