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Help needed please
2d Person who practices self-denial as a spiritual disciple ???e?i?
18a Acronym for frequencies below three kilohertz ?.t.?
No best answer has yet been selected by london_lassy. Once a best answer has been selected, it will be shown here.
For more on marking an answer as the "Best Answer", please visit our FAQ.Wilkipedia gives:-
ELF (Extremely Low Frequencies) 3-30Hz
SLF (Super Low Frequencies) 300-300Hz
ULF (Ultra Low Frequencies) 300Hz-3KHz
all the bove are below 3KHz so could be valid answers; (VLF is out as a range of 3KHz-30KHz is given) However of ULF, SLF & ELF isn't only the last (ELF) a true Acronym, the other two only being abbreviations?