The management of Recover Fast Hospital (RFH) claims that the average length of stay in their hospital after a major surgery is less than the average length of stay at General Hospital (GH). The following data have been accumulated to test their claim.

RFH GH

Sample Size 16 26

Mean(in days) 4 5

Standard Dev .5 .75

test to see if the average length of stay in RFH is significantly less than the average stay at GH. let a=0.05. what is the value of the test statistic

a. t=-4.716

b. z=-4.716

c. t=-3.123

d. z=3.123

e. non of these