In 2018, She had an average of 34 (SEM 6.7) trick or treaters an hour, for 4 hours. In 2019, she had an average of 42 (SEM 5.4) trick or treaters an hour, for 4 hours. Last year, 2020, she only had an average of 21(SEM 2.1) trick or treaters an hour, for 4 hours. 1. Was the number of trick or treaters for 2019 significantly different from 2018? 2. Was the number of trick or treaters for 2020 significantly different from 2018? (Please give detailed steps and explanation)