An ingot of germanium is formed by melting together 1 kg of germanium and 118 g of arsenic. (i) Assuming that the arsenic is uniformly distributed, calculate the number of arsenic atoms per unit of volume in the ingot. [You may use values for density of germanium: 5.46 g/cm, arsenic molar mass: 74.922 g/mol.] (ii) Assuming that the excess electrons due to the arsenic atoms are fully ionized at room temperature and that their mobility is 2,414 cm/V.s, calculate the conductivity (in S/cm) of the ingot. (iii)What resistance would you expect to measure for a bar of this material having a contact on either end and measuring 20 1 1 mm?