Answer
Even
Work Step by Step
If $f(-x)=f(x)$ then the function is even.
If $f(-x)=-f(x)$ then the function is odd.
If $f(-x)\neq f(x)$ and $f(-x)\neq -f(x)$ then the function is neither odd nor even.
$$f(x)=0.5x^4-2x^2+6$$ $$f(-x)=0.5(-x)^4-2(-x)^2+6=0.5x^4-2x^2+6=f(x)$$ Hence, it is even.
