South Tucson is actually the name of an independent, incorporated town of 1 sq mi (2.6 km2), completely surrounded by the city of Tucson, sitting just south of downtown. South Tucson has a colorful, dynamic history. It was first incorporated in 1936, and later reincorporated in 1940. The population consists of about 83% Mexican-American and 10% Native American residents. South Tucson is widely known for its many Mexican restaurants and the architectural styles which include bright outdoor murals, many of which have been painted over due to city policy.

Answer this question, if possible (if impossible, reply "unanswerable"): When was South Tucson reincorporated?
1940