Answer
a. 0, b. see explanations.
Work Step by Step
a. See graph, $\lim\limits_{x \to 0}h(x)=0$
b. As $cos(1/x^3)$ oscillates within $[-1,1]$ when $x\to 0$, and $\lim\limits_{x \to 0}x^2=0$, we have $\lim\limits_{x \to 0}x^2cos(1/x^3)=0\cdot\lim\limits_{x \to 0}cos(1/x^3)=0$,