Answer:
Mumbai and Kolkata
Explanation:
Bombay to Mumbai: Bombay's name was changed to Mumbai in 1996, deriving its name from Mumba or Maha-Amba — the name of the patron goddess (Kuladevata) Mumbadevi of the native Koli community. The oldest known names for the city are Kakamuchee and Galajunkja. Other names recorded in the 16th and the 17th centuries include Mombayn (1525), Bombay (1538), Bombain (1552), Bombaym (1552), Monbaym (1554), Mombaim (1563), Mombaym (1644), Bambaye (1666), Bombaiim (1666), Bombeye (1676), Boon Bay (1690),and Bon Bahia. After the English gained possession of the city in the 17th century, the Portuguese name was anglicised as Bombay.
Calcutta to Kolkata: Calcutta was renamed as Kolkata in 2001, after a bill was passed "in consideration of the historical, social and cultural aspects of the state and its capital city". The city is widely regarded as the "cultural capital" of India, and is also nicknamed the "City of Joy". The name is derived from Kolikata, the name of one of three villages that predated the arrival of the British; the other two being Sutanuti and Govindapur.