A researcher wants to study smart devices that track the number of hours of sleep the individual wearing it gets. A random sample of 40 individuals were recruited for this study. Twenty individuals wore the smart device while the other twenty individuals did not wear the smart device. For the individuals who wore the smart device, the sample average number of hours slept was 7.31 hours and a sample variance of 3.2 hours. For the individuals who did not wear the smart device, the sample average number of hours slept was 6.83 hours and a sample variance of 4.1 hours. is there a significant difference between the mean number of hours slept between the two groups?

Note: Here, Group 1 is the group that wore the smart device and Group 2 is the group that did not wear the smart device.

What is the alternative hypothesis? Explain.