Final answer:
HF stands for High Frequency (3-30 MHz), VHF for Very High Frequency (54-88, 174-222 MHz), and UHF for Ultra High Frequency (470-1000 MHz), with these ranges being used for different types of radio and television broadcasts.
Step-by-step explanation:
HF, VHF, and UHF stand for different ranges of frequencies used in radio and television broadcasting. HF refers to High Frequency, which typically covers the range of 3 to 30 MHz. VHF stands for Very High Frequency and includes TV channels that utilize frequencies in the range of 54 to 88 MHz for one group of channels and 174 to 222 MHz for another. Finally, UHF or Ultra High Frequency encompasses a higher frequency range used by other TV channels, specifically from 470 to 1000 MHz. It's important to note that these ranges are approximate, as exact frequency allocations can vary by country and specific services.