Two wires a and b of equal length and circular cross section are made of the same metal, but the resistance of wire b is four times that of wire a. what is the ratio between their spokes ? : a) rb / ra = 2, b) ra / rb = 2, c) rb / ra = 4, d) ra / rb = 16

An ice-making machine inside a refrigerator operates in a carnot cycle. it takes heat from liquid water at 0.0 degrees celsius and rejects heat to a room at a temperature of 19.2 degrees celsius. suppose that liquid water with a mass of 76.3kg at 0.0 degrees celsius is converted to ice at the same temperature. take the heat of fusion for water to be l_f = 3.34*10^5 j/kg.how much energy e must be supplied to the device? express your answer in joules.