Answer:
we used to use maps and compassed, now we can do all of that on our cell phones. also, the telescope has been turned into binoculars.
B. Voter turnout was very high, is the political parties were stronger, more people would vote and be confident to vote.
The harmonic frequency refers to the resonant frequency that is an integral multiple of the fundamental frequency, harmonics are usually simple sinusoidal oscillation at a single frequency. where as Resonance frequency are frequencies that are not necessarily sinosudal or integral multiple of fundamental frequency and it may have complex oscillations made up of multiple harmonics ~
It's like if you play a piano with a single key, it will show harmonic frequency, but if you use multiple keys at a time it may show Resonance.
plural it is talking about multiple things