Helium is unique in that as you cool it towards absolute zero at atmospheric pressure, it does not ever cross a phase transition in which it becomes a solid. Rather, 4He liquifies at 4.25K and continues to cool until it undergoes ANOTHER phase transition into a so-called superfluid phase at 2.17K. Superfluid 4He is a so-called quantum fluid, in that its properties diverge from a classical fluid in that they have strong wave-like properties. Problem 1.3. In order to have a quantum fluid, the de Broglie wavelength of the 4He must be larger than the average length scale between two neighboring helium atoms in the fluid, in that the helium is "delocalized" across the fluid. The average Lennard-Jones length scale of a4He4He interaction is approximately 0.26nm. What temperature must the helium be such that its thermal wavelength is greater than this length scale? Does this temperature agree with the observed quantum phase transition temperature of 2.17K