<span>node spacing = half of wavelength = 3 cm
velocity = 10 cm/s = freq * wavelength
hench freq = 10/6 = 5/3 = 1.7 hz</span>
D. White is a reflectiom of all colors
(20 N)/(2 m²) = (20/2) N/m² = 10 Pa
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The pascal (Pa) is the derived SI unit of pressure equal to 1 N/m².
I think the answer would be 70
