Tom and jerry can spend each day making dishes and building fences. if tom spends all day making dishes, he can make 16 dishes. if, instead, he devotes his day to building fences, tom can build 4 fences. if jerry spends his day making dishes, he can make 14 dishes; if he spends his day building fences, he can build 7 fences. the opportunity cost of one fence is for tom and for jerry. therefore tom should specialize in