In a simple linear regression analysis with n = 22 data points, an estimate ^1 = 56.33

In a simple linear regression analysis with n = 22 data points, an estimate β^1 = 56.33 is obtained with s.e.(β^1) = 3.78.
(a) Calculate a two-sided 95% confidence interval for the slope parameter β1s.
(b) Test the null hypothesis H0: β1 = 50.0 against a two-sided alternative hypothesis