Question: Suppose that in past years the average price per square metre for warehouses has been $322.80. A national real estate investor wants to determine whether that figure has changed now. The investor hires a researcher who randomly samples 19 warehouses that are for sale and finds that the mean price per square metre is $316.70, with a standard deviation of $12.90. If the researcher uses a 5% level of significance, what statistical conclusion can be reached? What are the hypotheses?