Exercises 19-22 refer to the small population of 4 cars listed in the table. Age (years) Color Red 1 White 5 8 20 Silver Red 19. Sample proportions List all 6 possible SRSS of size n = 2, calculate the pg proportion of red cars in each sample, and display the sampling distribution of the 477 sample proportion on a dotplot. Is the sample proportion an unbiased estimator of the population proportion? Explain your answer. 20. Sample minimums List all 6 possible SRSS of size n = 2, calculate the minimum age for each sample, and display the sampling distribution of the sample minimum on a dotplot. Is the sample minimum an unbiased estimator of the population minimum? Explain your answer. 21. More sample proportions List all 4 possible SRSS of size n = 3, calculate the proportion of red cars in the sample, and display the sampling distribution of the sample proportion on a dotplot with the same scale as the dotplot in Exercise 19. How does the variability of this sampling distribution compare with the variability of the sampling distribution from Exercise 19? What does this indicate about increasing the sample size? 22. More sample minimums List all 4 possible SRSS of size n = 3, calculate the minimum age for each sample, and display the sampling distribution of the sample minimum on a dotplot with the same scale as the dotplot in Exercise 20. How does the variability of this sampling distribution compare with the variability of the sampling distribution from Exercise 20? What does this indicate about increasing the sample size? 23. A sample of teens A study of the health of teenagers plans to measure the blood cholesterol levels of an SRS of 13- to 16-year-olds. The researchers will report the mean from their sample as an estimate of the mean cholesterol level in this population. Explain to someone who knows little about statistics what it means to say that is an unbiased estimator of u.