Can you calculate the probability of getting a sum of six when a dice is thrown twice?

What does this rebus mean?

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Suppose that you are trapped on the surface of a frozen lake. The surface is so smooth and ideal that there is no friction at all. You cant make any grip on the ice and no wind is blowing to help you out. You have just a mobile phone with you which has got no reception disabling you to call for help.

How will you plan your escape before you freeze to death on the frozen lake?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

In which direction should the missing arrow point?

There was an aeroplane crash, every single person died, but two people survived. How is this possible?

Can you solve this picture maths equation?

If it took eight men ten hours to build a wall, how long would it take four men to build it?

I am weightless, but you can see me. Put me in a bucket, and I'll make it lighter. What am I?

Here is what you have to do. You have to throw a ball as hard as you can but it must return back to you even if it does not bounce at anything. Also, you have nothing attached to the ball. There is no one on the other end to catch that ball and throw it back at you.

How will you do it?