Egg incubation helps chicks get out of their shells. Or for the people who have this question as a math problem, the answer is THE EGG SIT (the exit).
It falls and break
The egg will break in vinegar.
An egg will break if you sit on it or if some kind of force acts upon it...an egg will not just spontaneously break into pieces.
break the egg
Almost none. The egg might not break when falling to the ground but in the absence of incubation by the mother Robin, the egg has virtually no chance of surviving. If you find an intact egg that has fallen out of a nest in a tree, you may be able to incubate it artificially and a live chick will emerge.
a leaf
Breaking an egg is a physical change not a chemical one.
It is not the speed that breaks the egg. Rather, it is the force exerted on the egg due to acceleration when the egg hits some other object. An egg will break at a very low acceleration.
If you stand on an egg, it will break, regardless of it's position.
Yes, a bird's egg tooth is a temporary structure used to help the chick break through the eggshell during hatching. The egg tooth typically falls off or is absorbed shortly after hatching, as it is no longer needed once the chick has emerged from the egg.
A raw egg would break 'faster' but it depeneds on what you mean by faster. If you mean it would break easier then yes, it would be a raw egg. This is because a cooked egg's calcium shell has become harder, thus the term 'hard boiled egg'.