What does this rebus mean?

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Can you write down eight eights so that they add up to one thousand?

Find three whole, positive numbers that have the same answer when multiplied together as when added together.

Today is John's birthday.
A year ago, John had five candles and he lit all the candles except the one at the last.
Now he is going to light all the candles.

How old is John Today?

(He is not five today.....)

There's one "sport" in which neither the spectators nor the participants know the score or the leader until the contest ends.

What is it?

There once were seven dwarfs who were all brothers. They were all born two years apart. The youngest dwarf is seven years old. How old is his oldest brother?

It has a long neck, A name of a bird, Feeds on cargo of ships, It's not alive,

What is it?

What is common among 11, 69, and 88?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

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.