Choose the correct alternative for the missing term in the series: $BF, CH, ?, HO, LT$.

Choose the correct alternative to complete the series: $aab....aa....bbb....aaa....bbba$

Find out the wrong term from the given series:
$3, 4, 10, 32, 136, 685, 4116$

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 numbers are there in the above arrangement,each of which is immediately preceded by a consonant but not immediately followed by a consonant?

Find out the wrong term from the given series.
$11, 5, 20, 12, 40, 26, 74, 54$

Choose the correct alternative to complete the series: $...acca....ccca...acccc....aaa$