A tax specialist knows that tax refunds for people who use a firm to do their tax returns are normally distributed with a mean of $150 and a standard deviation of
$43. The specialist believes that the company, Taxco, uses under trained staff and gets a lower average tax refund for its customers. He takes a random sample of 6 customers from Taxco’s records and finds the following refunds:
Refund($)144, 38, 130, 160, 81, 135
Run a full hypothesis test at the 5% level of significance to test the tax specialists belief about Taxco.