What letters will fill the blank?

Z, X, V, T, R, __,__

Bhavin's birthday is on Monday 29th May. On what day of the week will be Rachit's Birthday in the same year if Rachit was born on 17th November?

A series is given, with one number missing. Choose the correct alternative from the given ones that will complete the series.
400, -200, 100, ? , 25, -12.5

A series is given, with one number missing. Choose the correct alternative from the given ones that will complete the series.
-7.25, -5.75, -4.25, -2.75, ? , 0.25

A series is given, with one number missing. Choose the correct alternative from the given ones that will complete the series.
49, 64, ?, 100, 121

A series is given, with one term missing. Choose the correct alternative from the given ones that will complete the series.
XIIIII, IXIIII, IIXIII, IIIXII,IIIIXI, ?

In the following question, select the missing number from the given series.
3, 7, 16, 35, ?

In the following question, select the missing number from the given series.
1, 3, 6, 10, 15, ?

In the following question, select the missing number from the given series.
13, 27, 56, 115, ?