A standing sound wave is created in a open tube. The pressure diagram for the air molecules of the standing wave is shown below.
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VII
Which of the labeled points is a displacement node?
Choose 1
I
IT
III
IV

i guess that visual aids present persuasive examples to what you are presenting, some factors would be theme (does it fit with the color, information, what you are presenting), size (can you see it, is it a big enough span of data/information), and overall look of the visual aid.

hope this : )

490 n

f=125n a=2.5m/s2