Answer the following questions about the standard normal random variable Z. (Use 4 decimal places in your answers to parts a. through f.) a. What is P(-1.5 < Z < 0.69)? .6754 Correct: Your answer is correct. b. What is P(0 < Z < 1.47)? .4278 Correct: Your answer is correct. c. What is P(Z > -1.62)? .9525 Correct: Your answer is correct. d. What is P(Z < -2.57)? .0052 Correct: Your answer is correct. e. What is P(Z < 2.57)? .9955 Correct: Your answer is correct. f. What is P(-2.49 < Z < -1.22)?

Farmers know that driving heavy equipment on wet soil compresses the soil and injures future crops. here are data on the "penetrability" of the same type of soil at two levels of compression. penetrability is a measure of how much resistance plant roots will meet when they try to grow through the soil. compressed soil 2.85 2.66 3 2.82 2.76 2.81 2.78 3.08 2.94 2.86 3.08 2.82 2.78 2.98 3.00 2.78 2.96 2.90 3.18 3.16 intermediate soil 3.17 3.37 3.1 3.40 3.38 3.14 3.18 3.26 2.96 3.02 3.54 3.36 3.18 3.12 3.86 2.92 3.46 3.44 3.62 4.26 use the data, omitting the high outlier, to give a 95% confidence interval for the decrease in penetrability of compressed soil relative to intermediate soil. compute degrees of freedom using the conservative method. interval: to