1.) You want to rent a one-bedroom apartment in San Jose, California next year. After looking at some listings on a property website, you find that the mean monthly rent for a random sample of 60 apartments is $1000 and the standard deviation is $200. Construct a 95% confidence interval.

2.) To what population of apartments can you appropriately infer from your sample in #1?

3.) How large a sample of one-bedroom apartments would be needed to estimate the population mean within plus or minus $50 with 90% confidence? (Note: use z-distribution; assumen > 30)

4.) If you decrease the sample size, while holding the confidence level the same, what will happen to the length of your confidence interval?

5.) Ms. de Zwart kept careful records of the fuel efficiency of her car. After the first 100 times she filled up the tank, she found the mean was 23.4 km per liter (km/L) with a standard deviation of 0.9 km/L. Compute the 95 percent confidence interval for the car's fuel efficiency.