Using a t-distribution calculator, it is found that the critical value for the hypothesis test is of t = 1.3277.
The critical value is found considering three inputs:
Hence, for a two-tailed test, with a 0.2 significance level and 19 df, the critical value is of t = 1.3277.
More can be learned about the t-distribution at https://brainly.com/question/16162795
#SPJ1