Two processes for hydraulic drilling of rock are dry drilling and wet drilling. In a dry hole, compressed air is forced down the drill rods to flush the cuttings and drive the
hammer. In a wet hole, water is forced down. As part of an analysis to determine the
cost of drilling a hole, an experiment was conducted in the Great-Karoo near Graaff-
Reinet to determine whether the time it takes to dry drill a distance of 5 meters in rock
increases with the depth at which drilling begins. The results for one portion of the
experiment are shown in Table 1.

At a sand and gravel plant, sand is falling off a conveyor and onto a conical pile at a rate of 16 cubic feet per minute. the diameter of the base of the cone is approximately three times the altitude. at what rate is the height of the pile changing when the pile is 12 feet high? (hint: the formula for the volume of a cone is v = 1 3 πr2h.)

There is a spinner with 14 equal areas, numbered 1 through 14. if the spinner is spun one time, what is the probability that the result is a multiple of 2 or a multiple of 5?

Quick! a survey of 57 customers was taken at a bookstore regarding the types of books purchased. the survey found that 33 customers purchased mysteries, 25 purchased science fiction, 18 purchased romance novels, 12 purchased mysteries and science fiction, 9 purchased mysteries and romance novels, 6 purchased science fiction and romance novels, and 2 purchased all three types of books. a) how many of the customers surveyed purchased only mysteries? b) how many purchased mysteries and science fiction, but not romance novels? c) how many purchased mysteries or science fiction? d) how many purchased mysteries or science fiction, but not romance novels? e) how many purchased exactly two types of books?