What does this rebus mean?

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Christina has four daughters, and each of her daughters has a brother. How many children does Christina have?

Can you find out the next digit in the following series ?

0, 0, 1, 3, 2, 6, 3, 9, 4, 12, 5, ?

Take away the whole and some still remain. What is it?

You’re out on the water and see a boat filled with people. You look away for a second and look back again, but this time you don’t see a single person on the boat. Why? Hint: The boat did not sink.

An exterior architect is asked by a builder to plant seven trees in a manner that there are exactly six rows of trees in a straight line and each row has three trees in particular.

How will he do it?

During an experiment, a guy throws a bouncy ball from a 100 feet tall building. The ball has a specific characteristic. Every time it hits the ground, it bounces up halfway.

How many bounces do you think the ball will make before it comes to a stop ?

Find out which of the given views in the picture is accurately the top view of the given pyramid.

What has one eye, but can’t see?

By moving just one matchstick, you need to make the below statement true. Can you do it?