g The compressive strength of concrete is normally distributed. A random sample of 12 concrete specimens from Factory 1 yields a sample mean equal to 1,284.5 pounds per square inch (psi) and a sample variance of 872.9 psi2. A random sample of 14 concrete specimens from Factory 2 yields a sample mean equal to 1,324.3 psi and a sample variance of 1,851.9 psi2. If you do a test of hypothesis to see if the means of the concretes from Factory 1 and Factory 2 are equal or not, what is the numerical value of the test statistic