Answer:
Scientist count the world humans population with an organization called The United Nations Population Division (UNPD),
Explanation:
Which keeps track of the world population, projects that the world's human population will hit 7 billion on Halloween Day 2011. Admittedly, that is just an estimate: There's no way to know exactly how many people are alive at any given moment, and the true date that humanity's ranks will surpass 7 billion could come in the weeks or months before or after Oct. 31. Nonetheless, the UN's guess is the best there is.
There is no picture of the bird.
In a Solid, particles are tighly packed together.
In a Liquid, they are farther apart
In a Gas, they are even farther apart.
*Melting = Liquid
*Freezing = Solid
* (E)vaporation = Gas
