Answer:
The population parameter of this study is the population mean.
Step-by-step explanation:
A population parameter is a numerical measure representing a certain characteristic of the population. For example, population mean, population variance, population proportion, and so on.
The population parameter is computed using all the values of the population.
The population parameter can be estimated using the sample statistic. If the value of the population parameter is not known, then a random sample of large size, say <em>n</em> ≥ 30 can be selected from the population and the statistic value can be computed. This statistic value is considered as the point estimate of the parameter. It is also known as the unbiased estimator of the parameter.
In this case the survey involved sampling of 1500 Americans to estimate the mean dollar amount that Americans spent on health care in the past year.
The sample selected is used to compute the sample mean dollar amount that Americans spent on health care.
So, the population parameter of this study is the population mean.
You have to use the fact that 
for any value of 
. So
where 
is the positive acute angle you're looking for.
It is A because x is less than one and it is open since there is no like underneath the sign.
