A researcher is investigating whether the cost of rental housing in San Francisco is the same as the cost of rental housing in the San Francisco Bay Area overall.

The mean monthly rent for a representative sample of 1,000 rental units in San Francisco is $3,500, with a standard deviation of $250. Official statistics from the state indicate that monthly rent for the whole Bay Area averages $3,050. The null hypothesis is that the population mean for San Francisco’s monthly rents is $3,050, the same as in the Bay Area overall. The researcher conducts a onetailed hypothesis test and fails to reject the null hypothesis. What alpha-level is the researcher using? Use the sample t-value to explain your answer.