The next term of the A.P 2, 6, 10, 14 is .
Find the sum of the first (i) 11 terms of the A.P.: 2,6,10,14,... (ii) 13 terms of the A.P.: -6,0,6,12,... (iii) 51 terms of the A.P.: whose second term is 2 and fourth term is 8.