Kamryn is deciding between three potential activities on saturday evening: 1) staying at home and watching her favorite television show, an activity that she values at $18 and that entails no out-of-pocket costs. 2) going to the movies with her sister to see the latest blockbuster action film, an activity she values at $30 and that entails $15 in out-of-pocket costs. 3) going out to dinner with her best friend, an activity she values at $40 and that entails $23 in out-of-pocket costs. a) which activity should kamryn choose?