During each four-hour period, a small town police force requires the following number of on- duty police officers: eight from midnight to 4 a.m.; seven from 4 a.m. to 8 a.m.; six from 8 a.m. to noon; six from noon to 4 p.m.; five from 4 p.m. to 8 p.m.; and four from 8 p.m. to midnight. Each police officer works two consecutive four-hour shifts. Determine how to minimize tire number of police officers needed to meet the town’s daily police requirements.