Answer
a. all the points except at $x=0$.
b. $x=0$
c. no points.
Work Step by Step
a. Examine the graph given by the exercise. We can find that all the points in the interval of the function are differentiable except at $x=0$. This is because the left derivative will be negative ($-\infty$) while the right derivative will be positive ($\infty$)
b. Examine the graph given by the exercise. We can find that one point at $x=0$ in the interval of the function is continuous but not differentiable. The function is continuous at this point because the left and right limits of the function are equal to the function value at this point.
c. Examine the graph given by the exercise. We can find that no points in the interval of the function are neither continuous nor differentiable,
