Can you fill the blank with the correct number?

6 30 870 756030 _____

Which number should replace the question mark?

What's the next in the series?

H, Be, F, S, Mn, Kr, In, Gd, Tl, ?

What runs around the whole yard without moving?

You need to pick one entry from pot A and one from pot B to have a perfect match. Can you do it?

A game is being played where eight players can last for thirty-five minutes. Six substitutes alternate with each player in this game. Thus, all players are on the pitch for the same amount of time including the substitutes.

For how long is each player on the pitch?

There are two guys standing face to face in a room. On a wall, there is a clock. One of those is a prophet. He tells the other guy that he will be stabbed in the back in five minutes.

Shocked to hear that, the other guy stares at the clock. Just after the five minutes, he is stabbed on the back. Can you tell what happened?

Only one color, but not one size,
Stuck at the bottom, yet easily flies.
Present in sun, but not in rain,
Doing no harm, and feeling no pain.
What is it?

In two decks of cards, what is the least amount of cards you must take to be *guaranteed* at least one four-of-a-kind?

What has a bottom at the top?