Summarizing the Distributional Derivative of a Piecewise Smooth Function

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Suppose $f\in C^1$. Define

$$g(x) = \begin{cases} f'(x) & \text{if $x\ne x_0$} \\ 0 & \text{if $x=x_0$} \end{cases}$$

(a) If $f$ is continuous at $x=x_0$, show that $f'=g$ in the sense of distributions

(b) If $f$ has a jump discontinuity at $x_0$ where

$$a=\lim\limits_{x \to x_0^-} f(x)$$ $$b=\lim\limits_{x \to x_0^+} f(x)$$

show that $f'=g+(b-a)\delta_{x_0}$ in the sense of distributions

I'm trying to proceed using definitions of distributional derivatives, continuity, and the delta function, but I can barely make sense of what the question is suggesting.

Any help is greatly appreciated!