A 2-wire d.c. distributor AB 500 metres long is fed from point A and is loaded as under: Distance from feeding point A (in metres) Load (amperes) 100 20 300 40 400 40 500 50 If the specific resistance of copper is 1-7 × 10 3 2m, what must be the cross-section of each wire in order that the voltage drop in the distributor shall not exceed 10 volts? [1-734 cm²]