Find the critical value(s) of t that would be used for the following independent measures t-test (assume that the null hypothesis is population mean 1 = population mean 2 with an alpha level of 0.05. What would the critical value be for n1=21, n2=21?

Find the critical value(s) of t that would be used for the following independent measures t-test (assume that the null hypothesis is population mean 1 = population mean 2 with an alpha level of 0.05. What would the critical value be for n1=21, n2=21?