Fill in the blank space for the given series with the correct alternative.
$840, 168, 42, 14, 7, (...)$

Study the following arrangement carefully,and answer the question given below:
$B, 2, I, J, K, 4, 3, H, 5, E, R, P, 6, N, A, 9, W, 8, T, U, 1, V, D, 7, F$
Which of the following is the third to the right of the tenth from the right end of the above arrangement?

Study the following arrangement carefully and answer the questions given below:

$7, R, E, T, 4, A, 9, \%, D, F, 1, U, \#, B, @, 8, H, I, \copyright, W, M, \star, 3, 2, V, \$, 5, N, P, 6, Q$

Which of the following is the fourth to the left of the twelfth from the left end?

One term in the number series is wrong. Find it.
$1, 5, 14, 30, 55, 93$

Find out the wrong term from the given series.
$125, 126, 124, 127, 123, 129$

Study carefully the following arrangement of letters, digits and symbols to answer these

questions.

$M, 7 ,\&, 8, L ,P ,@ ,Q ,N ,\beta ,T ,Y ,3 ,2 ,= ,E ,\$ ,4 ,9 ,\#, G ,H ,5$

If all the symbols are deleted from the arrangement, which of the following will be fourth to the left of the $17^{th}$ element from the left end ?