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: :
(1) What is the symbol of group 17?
(2) What is the symbol of group 1?
(3) What is the symbol of group 13?
(4) What is the symbol of group 13?
(5) What is the symbol of group 16?
(6) What is the symbol of group 2?
(7) What is the symbol of group 14?
(8) What is the symbol of group 7?
(9) What is the symbol of group 1?
(10) What is the symbol of group 16?