Can I see the graph so I can help you
Answer:
Density of iron is higher than the density of oxygen because iron is solid and the particles in it are very compact but oxygen is not dense as it is gas and particles in it are loosely packed.
A would be the wavelength, C would be a crest, D would be the amplitude, leaving B which is the trough.
Answer:
8437.5
Explanation:
By applying the formula of kinetic energy:
Kinetic energy=1/2 mv^2