What does this rebus mean?

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Yesterday I fell from 30 feet high ladder but I don't get hurt. Why?

Alex is stranded on an island covered in forest.
One day, when the wind is blowing from the west, lightning strikes the west end of the island and sets fire to the forest. The fire is very violent, burning everything in its path, and without intervention the fire will burn the whole island, killing the man in the process.

There are cliffs around the island, so he cannot jump off.

How can the Alex survive the fire? (There are no buckets or any other means to put out the fire)

You can hear me, but you can't touch or see me.

What am I?

Can you identify the famous TV character from the rebus below?

I’m tall when I’m young, and I’m short when I’m old. What am I?

Three friends decide to distribute the soda cans they had among them. When all of them had drunk four cans each, the total number of cans that remained was equal to the cans each one of them had after they had divided the cans.

Can you calculate the total number of cans before distribution?

Take one out and scratch my head, I am now black but once was red. What am I?

On rolling two dices (six-sided normal dice) together, what is the probability that the first one comes up with a 2 and the second one comes up with a 5?

What four weights can be used to balance from 1 to 30 pounds?