Divide:

$\frac{1}{4}{x}^2-\frac{1}{2}x-12$ by $\frac{1}{2}x-4$

Write the degree of each of the following polynomials:
$2x^2+5x^2-7$

"Note: This question given in the book seems to have errors and the modified question should be as given below."

Write the degree of each of the following polynomials:

$2x^3+5x^2-7$

Write the degree of the polynomial $5x^2-3x+2$.

Write the degree of the following polynomial:

$2x+x^2-8$

Write the degree of each of the following polynomials:

$\frac{1}{2}{y}^7-12y^6+48y^5-10$

Write the degree of each of the following polynomials:

$3x^3+1$

Write the degree of each of the following polynomials:

$5$

Write the degree of the following polynomial:

$20x^3+12x^2{y}^2-10y^2+20$

Which of the following expressions are not polynomials?

$x^2+2x^{-2}$