Arandom sample of 10 houses in a particular area, each of which is heated with natural gas, is selected and the amount of gas (therms) used during the month of january is determined for each house. the resulting observations are 139, 122, 141, 103, 138, 118, 99, 125, 89, 109. let μ denote the average gas usage during january by all houses in this area. compute a point estimate of μ.

Over the course of the school year, you keep track of how much snow falls on a given day and whether it was a snow day. your data indicates that of twenty-one days with less than three inches of snow, five were snow days, while of the eight days with more than three inches of snow, six were snow days. if all you know about a day is that it is snowing, what is the probability that it will be a snow day?