Answer:
The human ear is not sensitive to every frequency of sound, rather, our hearing range is from 20Hz to 20,000Hz. This means sound frequencies outside this range are not audible to the human ear, which is why not every sound produced is heard. This is quite a blessing because if we could hear every vibrating body, then our ears would never stop listening: we won't be able to distinguish 'important sounds' from unimportant ones, rendering our ears effectively useless. Perhaps this is why we have a hearing range in the first place: sounds of our friends and our foes lie in 20Hz-20kHz range.
A volcano erupts quietly if it's magma is low on silica. Low silica magma will be very thin, runny, and will flow easily, so the gases in the magma will bubble out gently. Hope this helps!:)
What do you mean you need to be more specific
Answer:
Hope it helps for you :)))))
6.022*10^23 atoms/mole of reactant
(this is chemistry not physics)
