I’m light as a feather, yet the strongest person can’t hold me for five minutes. What am I?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

All of the flowers I have are orchids except two. All of the flowers I have are hibiscuses except two. All of the flowers I have are roses except two.

Can you tell me how many flowers I have?

How can you make the following equation true by drawing only one straight line: 5+5+5=550 ?

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 a prime number.
The double of myself is equal to the square of me.

which number am I?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

A bomb goes off.
Carnage.
One person, only a few feet away, survives! How can this be?

Which word is least like the others? Third, fourth, fifth, sixth, seventh, eighth, ninth?

Can you find out which number multiplied by itself will give the output as 12345678987654321?