Differential Cost Analysis for Decision Making Rob Roberts has been working a summer job that pays $1,100 a month. His employer has offered to convert the job into a full-time position at $1.500 per month. Take- home pay is 70 percent of these amounts. In view of this offer. Rob is tempted not to return to school for the coming year. His friend Alice is trying to convince him to return to school. Rob remarks. "I've been talking to other friends, and no matter how you figure it, school is extremely expensive. Tuition is about $2.200 per year net of scholarship assistance. Books and supplies are another $600. Room and board will cost $3.700 a year even if I share a room. It costs $2.400 a year to keep up my car and clothing, and other incidentals amount to about $3,000 per year. I figure school will cost me the total of all these costs, which is $11,900 plus my lost salary of $18.000 per year. At $29.900 a year, who can justify higher education? If you were Alice, how would you respond to Rob's remarks?