The manager of the apartment complex in Problem 9 of Chapter 9 believes that the number of units rented during any given month has a triangular distribution with minimum 30, most likely 34, and maximum 40. Operating costs follow a normal distribution with mean $15,000 and a standard deviation of $300. Use Crystal Ball to estimate the 80%, 90%, and 95% confidence intervals for the profitability of this business. a. What is the probability that monthly profit will be positive? b. What is the probability that monthly profit will exceed $4,000? c. Compare the 80%, 90%, and 95% certainty ranges. d. What is the probability that profit will be between $1,000 and $3,000?