Choose the correct alternative to complete the series: $a \_ n \_ b \_ \,, \, \_ n c b \_ \,, \, \_ n c b$

Choose the term which will continue the following series :
$P 3 C , R 5 F , T 8 I , V 12 L , ?$

Fill in the blank space for the given series with the correct alternative.
$1, 2, 6, 24, (...)$

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 fill in the blanks in the series: $aab....ab...cabcca....bcab....c$

Find the missing letters for the given series from the given alternatives:
$aaa....bb....aab.....baaa....bb$