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

(N/A) The given expression $x^{3}+y^{3}+z^{3}-3xyz$ is a polynomial because the exponent of the variable in each of its terms is a non-negative integer (a whole number).
However,the expression contains three distinct variables: $x$,$y$,and $z$.
Therefore,it is a polynomial,but it is not a polynomial in one variable.