Complex sentence: The Rural Electrification Administration (REA) was established to devise a long-term solution to the seemingly intractable problem of extending electricity to rural Americans during the New Deal common in rural areas, so did automobiles and telephones.
Split into simpler sentences: The Rural Electrification Administration (REA) was established to devise a long-term solution to the seemingly intractable problem of extending electricity to rural Americans during the New Deal. As electricity become more common in rural areas, so did automobiles and telephones.