A biologist, studying the effect of an antibiotic on a particular kind of germ, examines the size of the "kill zone'l in a Petri dish by measuring the diameter of a clear area in the dish: the greater the diameter of the kill zone, the more effective the antibiotic. (a) She gathers data from 20 Petri dishes with the germ present and constructs a histogram of the diameters of the kill zones. MJBLIIGN Frequency N 0 l 2 3 4 5 6 7 8 Diameter (cm) (D How should she interpret this histogram? Q It appears that the data may be roughly normal, and the use of a normal probability plot may give a better look at whether the population is approximately normally distributed. 0 The data strongly indicate that the population is not normally distributed. 0 The data are clearly normally distributed; therefore, the population is normally distributed. 0 The histogram tells you nothing about the normality of the data. (b) Because the biologist, having seen the histogram of the kill zone diameter data from the 20 Petri dishes, believes the data may be from a population that is normally distributed, she decides to construct and examine a normal probability plot. 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 Diameter (cm) (3 How should she interpret this normal probability plot? 0 Because the points in this normal probability plot closely follow a line, it appears that the data are close to being normally distributed. 0 Because the points in this normal probability plot closely follow a line, the data are clearly not normally distributed, and the population is not normally distributed. 0 Because the points in this normal probability plot do not closely follow a line, the data are clearly normally distributed, and the population is normally distributed. 0 The normal probability plot tells you nothing about the normality of the data