If there are fifteen crows on a fence and the farmer shoots a third of them, how many crows are left?

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.

I am the black child of a white father, a wingless bird, flying even to the clouds of heaven. I give birth to tears of mourning in pupils that meet me, even though there is no cause for grief, and at once on my birth, I am dissolved into air. What am I?

Find The Next Number in this series.
1, 2, 6, 42, 1806 ?

Alpha is Beta's sister.

Gamma is a Beta mother.

Delta is Gamma's father.

Tango is Delta's mother.

Then,

How is Alpha related to Delta?

What do you get if you add 2 to 100 four times?

Can you find out the remainder when 3^300 is divided by 5?

What is the word or phrase below?
R | E | A | D

Can you find the ages of a son, father and grandfather based on the following facts?
The sum of the ages of grandfather, father and son is 140 years.
The age of the son in months is the same as the grandfather in years.
The age of the son in days is the same as the father in weeks.

Can you solve the tricky chess rebus puzzle below by ciphering the hidden meaning?