Travelocity would like to test if the average roundtrip airfare between New York and London is less than $1,400. A random sample of 30 flights between New York and London was selected and the airfare was recorded. Assume that the standard deviation for the population of airfares between these two cities is $230 and the true population mean for airfare is $1,330. Using = 0.10, beta equals ________.

A) 0.1655

B) 0.2483

C) 0.2730

D) 0.3483

can you help me step by step by hand please?