Eight of us go fourth, not back, to protect our king from an attack. What are we?

Solve the following series:
AZ, GT, MN, __, YB

A mother is 21 years older than her child. In exactly 6 years from now, the mother will be exactly 5 times as old as the child.
Where's the father?

Can you guess the name of the month by looking the below rebus ?

Can you find the dog hidden in a group of pandas?

I am a type of vehicle that has two wheels and is powered by humans. What am I?
Hint 1: You can ride me for exercise.
Hint 2: I am environment-friendly.

In a supermarket, there is an intelligent glass pane before a refrigerating unit. This glass pane allows cherries and apples through it but does not allow grapes and Orange to pass through it.

Can you identify the rule that the glass pane is following?

By moving exactly three matchsticks can you make the below equation true.It can be solved by 3 ways.

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

How is the moon similar to a dollar?