The magnetic moment of the earth is approx. 8x10^22 A m^2. Imagine that the planetary magnetic field were caused by the complete magnetization of a huge iron deposit with density 7900kg/m^3 and approximately 8.5x10^28 iron atoms/m^3. How many unpaired electrons, each with a magnetic moment of 9.27x10^-24 A m^2 would participate? T two unpaired electrons per iron atoms. How many kilograms of iron would be spent in the deposit?