What will come in place of the question mark (?) in each of the following series?

15     21    33    51     75    (?) 

Direction: Study the double bar graph given below and answer the questions.

The average of the number of students participating in exhibition is:

Direction:In question below has two blanks, each blank indicating that something has been omitted. Choose set of words for each blank which best fits the meaning of the sentence as a whole.
Since it does not have the ______ to do anything beyond sending out notices; the corporation has now decided to take steps to attach movable properties such as cars so that people take the notices more_____.

Noor forgot to bring her tiffin to school and asked Tanya to share her tiffin saying "You should share your tiffin with me today because I shared my tiffin with you yesterday". According to Lawrence Kohlberg's theory of moral development, Noor's statements represents_______ orientation typical at _______ stage. 

Which government body has decided to become paperless from the next session?

What should be the missing term in the following number series?
61, 67, 71, 73, 79, 83, __, 97,

On which river is the Boyoma waterfall located?

How many Sports Centre of Excellence will be opened in Itanagar?