Lots of people claim that having a pet helps lower their stress level. Researchers are interested in examining the effect having a pet. The researchers surveyed a total of 30 people. For n=18 participants who own a pet, the average well-being score was 15, with SS=320. For n=12 participant who do not have pets, the average well-being score was 18, with SS=240. Is there a significance difference between the two populations represented by these two samples with an alpha of 0.05? (Use the six-step procedure)