Choose the correct alternative to complete the series: $....a...b...abaa...bab...abb$

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

Fill in the blank space for the given series with the correct alternative.
$3, 10, 20, 33, 49, 68, (\ldots)$

Fill in the blank space for the given series with the correct alternative.
In the series $10, 17, 24, 31, 38, \ldots$,which of the following will be a number of the series?

These questions are based on the following arrangement. Study it carefully and answer the questions.
$8, H, \%, 3, 7, T, A, 4, \#, 6, B, I, @, R, 1, Q, \star, L, E, 2, K, \,U,5,9$
Four of the following five are alike in a certain way on the basis of their positions in the above arrangement and so form a group. Which is the one that does not belong to the group?

Find the missing letters for the given series from the given alternatives:
$b....ac....cc....cb...ab....ac$