4. In the last few years, the "resolution revolution" in cryo-electron microscopy has fundamentally changed the field of structural molecular biology, as it has the power to yield structures of large macromolecular assemblies, such as the spliceosome, approaching near-atomic resolution. To obtain a respectable 2.5 A structure of a macromolecular complex, (some examples currently exceed this), what voltage do you need in an electron microscope to accelerate the electrons used for imaging? (Hints: Think about the de Broglie equation, and how momentum, p=mv, is related to kinetic energy. You will need to know the mass and charge of an electron as well. For this problem, ignore relativistic effects to keep it simple.) a) Derive an expression for the potential (volts, V) in terms of Planck's constant, the wavelength, the mass of the electron and the charge of the electron. b) Calculate the voltage needed to produce electrons with a wavelength of 2.5 A