WILL MARK BRAINLIEST ACTUAL ANSWERS, PLZZZ

Part A:

Part B:

The closure property describes cases when mathematical operations are CLOSED. It means that if you apply certain mathematical operations in a polynomial it will still be a polynomial. Polynomials are closed for sum, subtraction, and multiplication.

It means:

But when it is about division:

Example of subtraction of polynomials:

Step-by-step explanation:

First, it is very important to define what is a polynomial in standard form:

It is when the terms are ordered from the highest degree to the lowest degree.

Therefore I can give:

but,

is not in standard form.

For this question, I can simply give the and it is correct.

But I will create a fifth-degree polynomial using this formula

Also, note that

For

Sorry but I will not type every step for each value of

The first one is enough.

For

Doing that for values:

f is the midpoint of

answer is x<