PDF chapter test TRY NOW

Which of the following are APs ?
 
(i) \(0.2, 0.22, 0.222, 0.2222, . . .\) is
 
(ii) \(0, – 4, – 8, –12, . . .\) is
 
(iii) \(\frac{-1}{2}, \frac{-1}{2}, \frac{-1}{2},...\) is
 
(iv) \(1, 3, 9, 27, . . .\) is
 
(v) \(a, 2a, 3a, 4a, . . .\) is
Answer variants:
not an arithmetic progression
an arithmetric progression