Why do atoms move at different speeds depending on weather they are in liquids or solids?

Exercise 2. find the wavelength of a photon emitted when an electron jumps from the n = 3 energy level down to the n = 2 energy level. where is this photon in the electromagnetic spectrum?

70 give a real life example showing how sensory neurons work with the motor neurons

What is the major limitation to the light microscope?