Fill in the blank space for the given series with the correct alternative.
$21, 25, 33, 49, 81, (...)$

To answer these questions, study the following arrangement of digits, letters and symbols carefully.

$6, N,P ,=,@, 7,1 ,\&, R, T, 3, L, ,B, \star, E ,4,\# ,8, G,H ,\$, 5, K,M ,?, 2, D,C$

If all the digits in the arrangement are deleted, which of the following will be midway between the $3^{rd}$ and the $15^{th}$ elements from the left end?

Find the missing term for the given series from the given alternatives:
$C, B, A, E, D, Z, G, F, (?)$

Fill in the blank space for the given series with the correct alternative.
$2, 6, 12, 20, 30, 42, 56, (\ldots)$

Choose the correct alternative for the missing term:
$MHZ, NIW, OKT, PNQ, ?$

Study of the following arrangement carefully and answer the questions given below.

$Q,E ,* ,P,M ,8 ,R,A ,@ ,C ,9 ,U,H,W, \# ,J,Z, ,S, \beta, Y,N ,5 ,\$ ,G,I,T$

What should come in place of the question mark $(?)$ in the following series based on the above arrangement?

$QP@,MAH,@YZ,?$