What value will come in place of question mark (?) in the questions given below?

663.48 + 22.51 - 292.63 = ? + 300.44 

What value will come in place of question mark (?) in the questions given below?

837 ÷ ? × 0.8 = 9.3 

Which is the smallest prime number? 

What will be remainder if (13)³ is subtracted from (66)² ?

What value will come in place of question mark (?) in the questions given below?
6⁹ × 36 ÷ 7776 = 6^? ÷ 216 

Direction : What value should come in place question mark(?) in the following questions?

0.75 % of 90 + 0.55 % of 80=?

What approximate value should come in place of question mark.
(1814 .9  ÷  121) x 35.78 ÷ 45.1023 = ? 

A man read 2/5 part of a book in 1st day, 34% in second day and remaining page in next two days. In two days he read equal number of page. If he read 52 page on last day, then find out how many page did the book contain?