A random sample of 49 medical doctors in LA showed that they worked an average of 53.1 hours/week with a standard deviation of 7.2 hours/week. If the California average is 60 hours/week, does this give evidence that the LA doctors work significantly less than the rest of California?

The manager of a sporting goods store offered a bonus commission to his salespeople when they sold moregoods. A new manager dropped the bonus system. For a random sample of six sales people, the weeklysales (in thousands of dollars) are shown in the following table with and without the bonus system

Salesperson 1 2 3 4 5 6

with bonus 2.9 3.0 5.8 4.4 5.3 5.6

w/o bonus 2.8 2.5 5.9 3.5 4.6 4.6

The following is based on information taken from Winter Wind Studies in Rocky Mountain National Park, by Glidden. At five weather stations on Trail Ridge Road in Rocky Mountain National Park, the peak wind gusts (mi/hr) in January and April are recorded below:

Weather station 1 2 3 4 5

January 139 122 126 64 78

April 104 113 100 88 61

Does this information indicate that the peak wind gusts are higher in January than April?