What occurs twice in a week, once in a year but never in a day?

Using eight eights and addition only, can you make 1000?

Can you count the number of lines in the below picture?

Assume there are approximately 5,000,000,000 (5 billion) people on Earth. What would you estimate to be the result, if you multiply together the number of fingers on every person's left hand? (For the purposes of this exercise, thumbs count as fingers, for five fingers per hand.) If you cannot estimate the number then try to guess how long the number would be.

How many sides does a circle have?

John was drowned by he was not wet. How?

I organized a small get together at my home.
In the party , i have a barrel with some whiskey in it.

Suddenly Guest 1 say 'I bet this barrel of whiskey is more than half full'.
'No, it's less than half full' Guest 2 replied.

I don't have any measuring instrument and without removing whiskey from it , how can i determine which of the guest is right ?

Count the number of balls in picture below:

What's the next in the series?

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

I am a three digit number.
My tens digit is five more than my ones digit.
My hundreds digit is eight less than my tens digit.
What number am I?