Question 384519
You want the null Ho to be very specific. So you want an equation in the null hypothesis. This means that we can rule out the last two choices. 



Now because we're doing a test on a population parameter, this means that we're going to be testing {{{mu}}} and NOT *[Tex \LARGE \bar{x}]. Why? Because we can very easily find the value of *[Tex \LARGE \bar{x}] for that given sample (since this is the sample mean), so there's no need to test it. However, we can't easily find the value of {{{mu}}}, which means that we need to test it. So this rules out the first choice.



So the answer is 


{{{H[o]}}}: {{{mu=16}}}
{{{H[A]}}}: {{{mu<>16}}}