The Economistand many other publications offer discounts to college students who sign up for subscriptions. At the current prices, the marginal revenue from the last subscription sold to college students is $15, and the marginal revenue from the last subscription sold to regular customers is $25.

The company sells its magazineto college students for only $15, because students' demand is _ than the other groups' demand.If the marginal cost of a subscription is $12, The Economistcan increase its profits by _.