Can u do the rest please

Part A

x⁴ + 2

You know this is in standard form because the powers of x decrease from left to right.

Part B

The closure property tells you that when you perform the operation (subtraction) on two members of the set (polynomials), the result is also a member of the set (a polynomial).

Example: (x³ + 2x) - (2x +1) = x³ -1

The difference of the two polynomials is also a polynomial.