Find the missing number

From the given options, find the number that comes in place of the question mark.

Which will be the blank term in the following series?

h_eg_fegh_eghfe_

Direction: In the following question, select the related letters from the given alternatives. 

QDXM : SFYN :: UIOZ : ?

Seven persons A, B, C, D, E, F and G are standing in a row facing the same direction. B is second to the right of C. B is extreme end of the row. Two persons between A and D. D is immediate left of C. Who is 4th from the right end?

The total strength of the class is 90 and the number of girls is twice that of boys. Suraj is ranked 14th from the top. Suppose there are 10 girls ahead of Suraj. Find the number of boys after Suraj in the ranking order.

Twenty students are standing in a straight-line facing North. Rina is standing sixth from the left end. There are only three students between Rina and Shweta. Radha is standing exactly between Shweta and Rina. Tina is standing sixth to the right of Radha. Anita is standing fourth from the right end of the line. There are more than four students between Rina and Tina.
How many people are standing between Anita and Tina?