The department shall devise and distribute a form for application for the program under sub. (2), shall determine eligibility for each 12-month benefit period of applicants and shall issue to eligible persons a prescription drug card for use in purchasing prescription drugs, as specified in sub. (5). The department shall promulgate rules that specify the criteria to be used to determine household income under sub. (2) (a) 4. and (b) and (3) (b) 1.