6.12 Assume the cost of an extended 100,000 mile warranty for a particular SUV follows the normal distribution with a mean of $1,600 and a standard deviation of $75.

a. Determine the interval of warranty costs from various companies that are 1.

one standard deviation around the mean.

2. two standard deviations around the mean.

3. three standard deviations around the mean. b. You see an ad for an extended warranty for this type of vehicle for $1,900. Based on the previous results, what conclusions can you make?