Lily is a dancer earning $37.8 an hour. Her new favourite movie has just been released and costs $30.2. She is considering whether to buy it, call in sick for a 2-hour-long shift and watch it. If she goes to work, she expects to earn an additional $38 in tips. She could also go to the pool for a swim and a sauna session, which she values $36. What is Sarah's opportunity cost of buying and watching the movie?