calculate the average drift speed of electrons traveling through a copper wire with a cross-sectional area of 40mm² when carrying a current of 20A. Assume one electron per atom of copper contributes to the current. The atomic mass of copper contributes to the current. The atomic mass of copper is 63.5g/mol and its density is 8.93 g/cm³. Avogadros number is 6.022 x 10²³ and the fundamental charge is 1.602 x 10^-19 C. Answer in units of m/s