In johannesburg, south africa, the south west township (soweto) was one of several areas established early in the last century for blacks to live away from the white ruling minority. on the hills surrounding soweto, the company that provides south africa's electricity, eskom, built a large, coal-burning, electricity-generating plant. the electricity was for white areas of johannesburg, miles away from the plant. the residents of soweto had no electrical connections. things have improved in soweto in the past 10 years. however, even in areas where electricity is available, as of 2002 it typically costs up to ten times more per kilowatt-hour for electricity in soweto than for electricity to nearby industries, and over 30% more than in the nearby white suburban areas. a possible reason for this is that
a. gas-powered home generators
b. wood and coal
c. natural gas and backyard windmills
d. charcoal and candles
e. natural gas and solar cells