Choose the correct alternative answer

$a...bbbc...aab....cca....bbcc$

To answer these questions,study carefully the following arrangement of letters,digits,and symbols:
$6, =, *, C, E, 3, 8, G, L, M, 7, \star, @, P, R, 4, !, N, T, 5, S, V$
How many such letters are there in the arrangement,each of which is immediately followed by a symbol?

Choose the correct alternative for the missing term in the series: $AZ, GT, MN, ?, YB$

Choose the correct alternative to complete the series: $a . c a . b e . b c c . . . b c a$

Fill in the blank space for the given series with the correct alternative.
$11, 13, 17, 19, 23, 25, (\ldots)$

Choose the correct alternative for the missing terms in the series: $A, Z, X, B, V, T, C, R, ?, ?$