6. Match each recursive function with the equivalent explicit function. f(n) = 6(7-1); f(n) = 12 + 6n; f(n) = 12(7-1); f(n) = 6+ 12n; n21 n21 n21 n21 f(1) = 18; f(n) = f(n- 1) +6; O O 0 n2 2 f(1) = 18; f(n) = f(n- 1) + 12; 0 n2 2 f(1) = 1; f(n) = 6f(n - 1); 0 nz2 f(1) = 1; f(n) = 12f(n - 1); 0 0 0 12 2