Help please and answer A-D

A: Label each wave above as transverse or longitudinal.
B: Which wave above could be used to represent a sound wave?
C: Which wave above is used to represent an electromagnetic wave?
D: Which wave above is also a model for light waves?

The size (radius) of an oxygen molecule is about 2.0 ×10−10m. make a rough estimate of the pressure at which the finite volume of the molecules should cause noticeable deviations from ideal-gas behavior at ordinary temperatures (t= 300k ). assume that deviatons would be noticeable when volume of the gas per molecule equals the volume of the molecule itself.