By definition we have to:
A set has under an operation if performance of that operation on set members always produces a member of the same set; in this case we also say that the set is closed under the operation.
For this case we have the following polynomials:

Multiplying we have:

The product of two polynomials is also a polynomial.
Answer:
d
is a polynomial
180 is the lcm for 20 and 18
Answer:
7 students play an instrument.
Calculation:
35=100%
20%=[20×35]÷100
=7
Answer:
no
Step-by-step explanation:
-2 is less than 4 2/3
you can check this by looking at a number line