Summarizing numerical data sets Practice Test

Consider the following data set:

$\left \{ 1, 3,3, 4, 5, 5, 6, 8, 9, x, x \right \}$

where is an integer from 1 to 10 inclusive.

How many possible values of make 5 the median of the set?

Donna will take twelve tests in her biology class, worth one hundred points each. Her score for the term will be the arithmetic mean of the best ten.

She has taken eleven tests already; her scores, in order, are:

74, 79, 60, 77, 54, 80, 81, 60, 66, 68, 71

How high will Donna have to score on the twelfth test in order to get a "B" in the course, which is defined to be a mean of 80 points?

Note: Assume that no extra credit is given on any test.