B. acidity...
hope this helps and HAGD!
The answer should be the third option "number of protons and neutrons." The atomic mass of a element is equal to the amount of protons, and neutrons added together in that element. So for example if we are trying to find the atomic mass of hydrogen you would add the total amount of protons and neutrons together to find it's mass although it doesn't equal the exact amount of it's mass but it's close.
Hope this helps.
C. Enzymes increase the rate of the chemical reactions carried out during metabolism.
D.
If the vibrations have a low frequency, the sound is heard as a __low-pitched sound_____. If the vibrations have a high frequency, then the sound is heard as a __high-pitched sound_____.
Explanation:
High pitched sound is of higher frequency because they make the air molecules vibrate much faster than low-pitched sound. Due to their high frequency, their wavelength is shorter (Remember wavelength and frequency are inversely proportional). Vice versa is true to the low-pitched sound. They vibrate air molecules slower than high-pitched sound. Their wavelength is longer and frequency smaller.
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For mor on pitch of sound check out;
brainly.com/question/61859
brainly.com/question/1509263
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