Answer:
a. p = the population proportion of UF students who would support making the Tuesday before Thanksgiving break a holiday.
Step-by-step explanation:
For each student, there are only two possible outcomes. Either they are in favor of making the Tuesday before Thanksgiving a holiday, or they are against. This means that we can solve this problem using concepts of the binomial probability distribution.
Binomial probability distribution
The binomial probability is the probability of exactly x successes on n repeated trials, and X can only have two outcomes.

In which
is the number of different combinatios of x objects from a set of n elements, given by the following formula.

And p is the probability of X happening.
So, the binomial probability distribution has two parameters, n and p.
In this problem, we have that
and
. So the parameter is
a. p = the population proportion of UF students who would support making the Tuesday before Thanksgiving break a holiday.
Answers: choice C and choice E
Plugging x = 3 and y = -1 into both equations of choice C lead to a true result (the same number on both sides). This is why the system of equations listed in choice C is one possible answer. Choice E is a similar story.
If your teacher didn't mean to make this a "select all that apply" type of problem, then it's likely your teacher may have made a typo.
2x + y = 5
x − 2y = 10
y = 5 − 2x
x − 2(5 − 2x) = 10
x − 10 + 4x = 10
5x − 10 = 10
<em>add 10 to each side</em>
<em>5x-10+10 = 10 + 10</em>
<em>5x=20</em>
5x = 0 <em>this is the error</em>
He needs to add 10 to each side