(c) Use these commands to download the packages needed for hypothesis tests library(car); library(Imtest); library(sandwich); = Test the hypotheses below by t-tests (using either the critical t-values or the p-values) at the 5% level of significance. (i) H.:B2 = 0 against the alternative that the coefficient is negative. (ii) H.:B3 = 0 against the alternative that the coefficient is positive. The alternative is 1-sided in either case, so the applicable p-values are half of the 2-sided p-values in the R output. - The critical t-value leaving a % probability under the upper-tail of the t-distribution with v degrees of freedom can be found by the R command qt(1-a , df=v); Modify this command as needed to find the required critical values, e.g., qt(0.9, df=40); for a distribution with 40 degrees of freedom and leaving 10% area under the upper tail. (c) Use these commands to download the packages needed for hypothesis tests library(car); library(Imtest); library(sandwich); = Test the hypotheses below by t-tests (using either the critical t-values or the p-values) at the 5% level of significance. (i) H.:B2 = 0 against the alternative that the coefficient is negative. (ii) H.:B3 = 0 against the alternative that the coefficient is positive. The alternative is 1-sided in either case, so the applicable p-values are half of the 2-sided p-values in the R output. - The critical t-value leaving a % probability under the upper-tail of the t-distribution with v degrees of freedom can be found by the R command qt(1-a , df=v); Modify this command as needed to find the required critical values, e.g., qt(0.9, df=40); for a distribution with 40 degrees of freedom and leaving 10% area under the upper tail