Can you fill the blank with the correct number?

6 30 870 756030 _____

In case you were starting to feel confident, this one was meant for third graders in Vietnam. The answer is 66, but we don't blame you for scratching your head about how they got there.

Can you complete the sequence puzzle?

AR TA GE CA LE VI LI _

It comprises roots which nobody sees,
Much taller than those trees,
Up and up it goes,
Still it never grows?

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?

He does not have any heart but still, He manages to live.
If you kill him, you will eventually die but yet you kill him.
He cannot run, who is He?

If two fifty-foot ropes are suspended from a forty-foot ceiling that is twenty feet apart, how much rope will you be able to steal if you have a knife?

What has six faces, but does not wear makeup, has twenty-one eyes, but cannot see? What is it?

I have some blue and red sock in my drawer. I have a total of 4 socks. I pick 2 socks and the chance that I get a pair of red socks is 1/2.

What is the chance of picking a pair of blue socks?

What runs around the whole yard without moving?