Read the passage given below and answer following five question :
AIR has evolved, over the years, a three-tier system of broadcasting namely national, regional, and local. It caters to the information, education, and entertainment needs of the audrence through its stations in this country of continental dimension with plural society. They provide news, music spoken words, and other programmes in 23 languages and 176 dialects to almost the entire population of the country which crossed 1 billion mark recently.
The entertainment channel of AIR named Vividh Bharati was started on October 3, 1957 and since November 1, 1967, commercials were aired on this channel. The first Radro Sangeet Sammelan was organised in 1954, which has since become an annual feature. Akashvani Annual Awards to promote excellence in Programme, Engineering, News and Audrence Research were instituted in 1974. Doordarshan was separated from AIR on April 1, 1976. The first broadcast by political parties before elections went on-air in 1977 from different stations of AIR. The North Eastern Service was commissioned on January 3, 1990 at Shillong in the campus of AIR, Shillong. The public service broadcasting initially in the evening transmission for about five and a half hour dally has since been extended to three trasnmissions. The programmes are beamed through a 50 kw SW transmitter in Hindr and English besides music programmes in different languages/dialects of all the states of the North East.