You have sold 72, and your friend has sold 74. Meaning your friend has sold 2 more magazine subscriptions than you.
Answer:
The value of the test statistic is -2.64.
Step-by-step explanation:
The test statistic is:

In which X is the sample mean,
is the expected(claimed) mean,
is the standard deviation and n is the size of the sample.
An automobile manufacturer claims that its van has a 40.3 miles/gallon (MPG) rating.
This means that 
After testing 250 vans, they found a mean MPG of 39.9. Assume the standard deviation is known to be 2.4.
This means, respectively, that:

So



The value of the test statistic is -2.64.
26.60 if not
so sorry im also very small brain like u
I don't know the first one but the second one is The second national bank was chartered in 1816.