A parallel $\mathrm{L}-\mathrm{C}$ circuit comprises of a $5\mathrm{H}$ inductor and $5 \mathrm{\mu F}$capacitor. Calculate the resonant frequency of the circuit.

A capacitor of capacitance $0.5 \mathrm{\mu F}$ is connected to a source of alternating e.m.f. of frequency $100 \mathrm{Hz}$. What is the capacitive reactance? $(\pi = 3.142)$