Suppose that a defined population is all men who are 50 or younger and a survey is being conducted which of these is an example of selection bias

Awall map has a scale of 128 miles = 6 inches. the distance between springfield and lakeview is 2 feet on the map. what is the actual distance between springfield and lakeview? 384 miles 512 miles 1.13 miles 42.7 miles

Lucy is a dress maker. she sews \dfrac47 7 4 of a dress in \dfrac34 4 3 hour. lucy sews at a constant rate. at this rate, how many dresses does lucy sew in one hour? include fractions of dresses if applicable

The distribution of the amount of money spent by students for textbooks in a semester is approximately normal in shape with a mean of $235 and a standard deviation of $20. according to the standard deviation rule, how much did almost all (99.7%) of the students spend on textbooks in a semester?