[[align=center]align=center][align=left]A standing wave is formed when ____.[/align]
[motr1]اختر الاجابة الصحيحة :[/motr1]
a. a wave refracts due to changes in the properties of the medium.
b. a wave reflects off a canyon wall and is heard shortly after it is formed.
c. red, orange, and yellow wavelengths bend around suspended atmospheric particles.
d. two identical waves moving different directions along the same medium interfere.
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