What four weights can be used to balance from 1 to 30 pounds?

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?

John’s parents have three sons: Snap, Crackle, and what’s the name of the third son?

Pronounced as one letter,
And written with three,
Two letters there are,
And two only in me.
I am double, I am single,
I am black blue and grey,
I am read from both ends,
And the same either way.

Take away my first letter, then take away my second letter. Then take away the rest of my letters, yet I remain the same. What am I?

I am not alive, but I grow; I don't have lungs, but I need air; I don't have a mouth, but water kills me. What am I?

Two girls were born to the same mother, on the same day, at the same time, in the same month and year and yet they're not twins. How can this be ?

Can you decipher the two rows to find the hidden word?

A father's child, a mother's child, yet no one's son.

Who am I?

I have eight fingers and two thumbs but I do not live. What Am I?