Which of the following expressions are polynomials in one variable and which are not? State the reason for your answer. If the given expression is a polynomial,state whether it is a polynomial in one variable or not: $\pi x^{2}-\sqrt{3} x+11$

(A) The given expression is $\pi x^{2}-\sqrt{3} x+11$.
$1$. $A$ polynomial is an algebraic expression in which the exponents of the variable are non-negative integers.
$2$. In the expression $\pi x^{2}-\sqrt{3} x+11$,the exponents of the variable $x$ are $2$,$1$,and $0$ (since $11 = 11x^{0}$).
$3$. Since all exponents are non-negative integers,the expression is a polynomial.
$4$. Since the expression contains only one variable,$x$,it is a polynomial in one variable.