David wants to estimate the difference in mean lengths of Science Fiction (SciFi) and Thriller novels. He randomly samples 30 SciFi novels and records the length (in number of pages) for each novel. He then randomly samples 30 Thriller novels and records the length (number of pages) for each. Use the information from the summary table below to complete the exercise.

DifferenceSample MeanStandard ErrorDegrees of FreedomSciFi-Thriller148.521.950

• What type of samples were selected?
• independent samples
• dependent samples
• Consider a 99% level of confidence. The t-critical point to use is t =. (Report to 3 digits after the decimal.)
• Calculate the lower and upper limits: lower limit =, upper limit =(Round to 2 decimal places.)
• Which of the following conclusions is correct for the interval calculated?
• With 99% confidence, we estimate the mean number of pages in Science Fiction novels is less than the mean for Thriller novels by some amount between the limits calculated above.
• With 99% confidence, there is no evidence of a difference in the mean number of pages in the two types of novels.
• With 99% confidence, we estimate the mean number of pages in Science Fiction novels is more than the mean for Thriller novels by some amount between the limits calculated above