a. X ~ N(-1, 0.5) σ = Round to the nearest one decimal place if necessary.
b. Suppose X ~ N(9, 3). What is the z-score of x = 7? Round the answer to two decimal places if necessary.
c. Suppose X ~ N(2, 3). What value of x has a z-score of -0.67? Round the answer to one decimal place if necessary.