Is the classification for an instrument that produces sound
by the vibration of a tightly stretched membrane.
o
a. chordophone
o
o
b. aerophone
c. membranophone
o
d. idiophone

Membranophone

Explanation:

Membranophone, any of a class of musical instruments in which a stretched membrane vibrates to produce sound. Besides drums, the basic types include the mirliton, or kazoo, and the friction drum (sounded by friction produced by drawing a stick back and forth through a hole in the membrane).

including the octave, the answer would 8 notes in a major scale with one note being played twice. ex) c major scale includes: c, d, e, f, g, a, b, c

notice that c is played twice

however, if you were to ask me how many different notes are in a major scale- the answer would be 7.  

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