Soundex produces x model a radios and y model b radios. model a requires 15 min of work on assembly line i and 10 min of work on assembly line ii. model b requires 10 min of work on assembly line i and 12 min of work on assembly line ii. at most, 25 labor-hours of assembly time on line i and 22 labor-hours of assembly time on line ii are available each day. it is anticipated that soundex will realize a profit of $10 on model a and $12 on model b. how many clock radios of each model should be produced each day in order to maximize soundex's profit?