20. The university computer lab is having difficulty controlling its costs, but is also concerned with revenues. Analysis showed that a key issue is the cost of printer supplies (ink, paper, and machine repair). Which strategy is likely to create the greatest amount of revenue for the lab, if a typical student use is 200 copies per month? A. Plan A: requiring students to pay 12 cents per copy B. Plan B: charging a fee of $20 for the first 100 copies per month, then 10 cents per copy thereafter C. Plan C: charging a fee of $10 for the first 50 copies per month, then 15 cents per copy thereafter D. Plan D: adding a flat lab fee of $30 per academic term E. All of the choices are correct