Which of the following are AP's ? If they form an AP, find the common difference d and write three more terms.
(i) `2, 4, 8, 16, . . .`
(ii) `2,5/2,3,7/2,. . .`
(iii) ` -1.2 ,- 3.2 ,- 5.2 ,- 7.2 ,...`
(iv) ` -10 ,-6,-2,2....`
(v) `3,3+sqrt2,3+2sqrt2,3+3sqrt2,..." "`
(vi) `0.2,0.22,0.222,0.2222,..." "`
(vii) `0,-4,-8,-12,..." "`
(viii) `-(1)/(2),-(1)/(2),-(1)/(2),-(1)/(2),..." "`
(ix) `1,3,9,27,..." "`
(x) `a,2a,3a,4a,..." "`
(xi) `a,a^(2),a^(3),a^(4),..." "`
(xii) `sqrt2,sqrt8,sqrt18,sqrt32,..." "`
(xiii) `sqrt3,sqrt6,sqrt9,sqrt12,..." "`
(xiv) `1^(2),3^(2),5^(2),7^(2),..." "`
(xv) `1^(2),5^(2),7^(2),73,...`