In physics 1, you have learned about the particle-wave duality of matter. You can think of light as a wave or a particle called a photon. So let's take a beam of neutrons and consider its wave-like character. In an experiment, I want to study a lipid membrane which is 5nm thick and has an index of refraction very near 1 for neutrons. What is the largest wavelength neutrons I should use to see an interference maximum with the neutron beam normal to the lipid membrane?