Choose the correct alternative to fill in the blanks in the series: $....bbca....bcca......ac.....a...cb$

Fill in the blank space for the given series with the correct alternative.
$462, 420, 380, (...), 306$

Study the following arrangement carefully and answer the question given below:
$B, 2, I, J, K, 4, 3, H, 5, E, R, P, 6, N, A, 9, W, 8, T, U, 1, V, D, 7, F$
Four of the following five are alike in a certain way and so form a group based on their positions in the given arrangement. Which is the one that does not belong to this group?

Study the following arrangement carefully and answer the question given below:
$R, 4, E, J, 5, T, 1, A, M, Q, 3, 8, N, I, K, 7, W, F, 6, D, 9, U, 2, Y, V$
How many such vowels are there in the above arrangement,each of which is immediately preceded by a number and immediately followed by a consonant?

Find out the wrong term from the given series.
$1236, 2346, 3456, 4566, 5686$

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