MUMBAI, March 15 (Reuters) - India will sell 120 billion rupees ($1.85 billion) of treasury bills, including 70 billion rupees of the 91-day t-bills, and 50 billion rupees of the 364-day t-bills, on March 20, the Reserve Bank of India said on Friday. ($1=54 rupees) (Reporting by Shamik Paul; Editing by Bijoy Koyitty)