1. State the hypotheses.
2. Find and the critical region.
3. Find . Also, draw a standard normal curve showing , the critical region, and .
4. State the conclusion and the interpretation.

54. Online Shopping. The Nielsen organization reports that smartphone owners spent a mean of 93 minutes using shopping apps on their smartphones in the fourth quarter (last three months) of 2013. A random sample of 225 smartphone owners showed a mean of 99 minutes using shopping apps on their smartphones in the fourth quarter of last year. Assume . Conduct a hypothesis test, using level of significance , to determine whether the population mean amount of time has changed.