Fill in the blank space for the given series with the correct alternative.
$3, 9, 27, 81, (\ldots)$

Choose the correct alternative to fill in the blanks in the series: $...,...aba..., ...ba ...ab$

If $2$ is subtracted from each odd digit and $3$ is added to each even digit in the number $3675249$,how many digits will appear twice in the new number thus formed?

Choose the correct alternative for the missing terms in the sequence: $Z, L, X, J, V, H, T, F, ?, ?$

Choose the correct alternative to fill in the blanks in the series: $c . . b b a . . . . c a b . . . . a c . . . . a b . . . . a c$

Find out the wrong term from the given series.
$52, 51, 48, 43, 34, 27, 16$