Answer
a. Yes.
b. Yes.
Work Step by Step
In an LRC circuit, the rms voltages across an inductor or a capacitor can be greater than the rms source voltage. As discussed on page 615, the different voltages are out of phase with each other, and the rms values do not add up to the source voltage. See Figure 21-44 for a phasor diagram.
a. For a high frequency where the inductive reactance $X_L=2\pi f L$ has a high value, the rms voltage across the inductor can be greater than the rms voltage of the source. This is actually realized in Example 21-15.
b. For a low frequency where the capacitive reactance $X_C=1/2\pi f C$ has a high value, the rms voltage across the capacitor can be greater than the rms voltage of the source.