Find the missing letters for the given series from the given alternatives.
$ba.....ba.....bac......acb......cbac$

Which number will come next in the following series?
$2, 1, 2, 1, 3, 2, 1, 3, 4, 2, 1, 3, 4, 5, 2, 1, 3, 4, 5, 6, 2, 1, 3, 4, 5, ?$

These questions are based on the following letter/number/symbol arrangement. Study it carefully and answer the questions that follow.

$5, D,H,E, \star, 7,9, \$ ,F,I ,6 ,R ,\% ,L ,1 ,A,J, 3, B, \# ,4 ,@ ,K,P ,8, U,M, 2$

What will come in place of the question marks $(?)$ in the following series based on the above arrangement?

$E,D,H ,9 ,\star, 7, I,\$,F, ?, ?, ?$

Choose the correct alternative to complete the series: $....abb....bb....a....bbab....ba$

Find out the wrong term from the given series.
$1, 2, 6, 15, 31, 56, 91$

Choose the correct alternative for the missing terms in the series: $R, M, ?, F, D, ?$