Which of the following is a quadrilateral?

7, ____, 21, 28,35.

Which is the longest two digit number?

12A,13B,14C,_____.

Find the odd one:

If A D B O C G  is coded as D O G, then A B B O C O D K is coded as.

If 2 O 2 X 2 is coded as OX, then 2 C 2 A 2 T 2 is coded as.