When did AC/DC start?
1973
1973
1973
1973
1973
1973
1975
1973
1975
1973
1975
1973
1975
1973
1975
1973
1975
1973
1975
1973
1975
1973
1975
1973
1975
1973
1975
1973
1974
1976
1975
1973
1974
1976
1972
1975
1973
1974
1976
1972
1975
1973
1974
1976
1972
1975
1973
1974
1976
1972
1975
1974
1976
1972
1975
1974
1976
1972
1975
1974
1976
1980
1972
1975
1979
1974
1976
1980
1977
1972
1971
1975
1979
1974
1976
1980
1977
1972
1971
1979
1974
1976
1980
1977
1972
1971
1979
1974
1976
1980
1977
1972
1971
1979
1974
1976
1980
1977
1972
1971
1979
1970
1974
1976
1980
1977
1972
1971
1979
1970
1974
1976
1980
1977
1972
1971
1979
1970
1973.
1974
1976
1980
1977
1972
1971
1979
1970
1974
1976
1980
1977
1972
1971
1979
1970
1974
1976
1980
1977
1972
1971
1979
1970
1975.
1974
1976
1980
1977
1972
1971
1979
1970
1974
1976
1980
1977
1972
1971
1973.
1979
1970
1980
1977
1972
1971
1979
1970
1980
1978
1977
1971
1979
1970
1980
1978
1977
1971
1975.
1979
1970
1964
1980
1978
1977
1971
1973.
1979
1970
1964
1980
1978
1977
1971
1979
1970
1964
1972.
1974.
1975.
1973.
1976.