Identify the hidden meaning behind this picture?

There are people and strange monkeys on this island, and you can not tell who is who (Edit: until you understand what they said - see below). They speak either only the truth or only lies.
Who are the following two guys?
A: B is a lying monkey. I am human.
B: A is telling the truth.

A brand new Mobile Phone was on sale at 20% as a promotional offer. By what per cent must the Mobile price be increased to sell it at the original price again?

Spelt forwards I’m what you do every day, spelled backwards I’m something you hate. What am I?

In the figure, you can see nine stars. What you have to do is connect all of them by using just four line and without lifting your hand i.e. in a continuous flow.

A red house is made out of red bricks. A yellow house is made out of yellow bricks. And, a blue house is made out of blue bricks. So, what is a greenhouse made of?

It is deaf, Dumb and Blind!!!

Still, always tells the truth. What is it?

Look at this sequence from top to bottom. What is the next number in the sequence?
1
11
21
1211
111221
312211

The answer I give is yes, but what I mean is no. What was the question?

John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?