Answer:
Estimates of historical world population
Year 1400 1600
population (in billions) 0.35–0.40 0.50–0.58
growth p.a. >0% 0.15–0.3%
Question: When an atom that has no charge loses two electrons, it becomes a:
A: positive ion.
B: negative ion.
C: positive isotope.
D: negative isotope.
Answer:
When an atom that has no change loses two electrons, it becomes "positive ion".
Explanation:
It is known that electrons hold a negative charge. So, when the negative charge that is electrons are taken out an atom then the number of electrons become less in number as compared to the number of protons. Hence, the atom attains a positive charge.An isotope is formed when an atom shows same number of protons and different number of neutrons. So, when an atom loses 2 electrons there will be no change in the number of neutrons. Therefore, an isotope will not form.Thus, it is concluded that when an atom with no charge loses two electrons, it becomes a positive ion.
The answer is C. decreases.
C-14 and C-12 are carbon isotopes used to measure the approximate age of organic remains. C-12 is stable, and it does not break down into other elements over time. C-14 is not stable. It breaks down into N-14.
Organisms can incorporate C-14 into their bodies during the life. But when the die, C-14 is not incorporated anymore. After organisms' death, C-12 will remain stable, but C-14 will start to breaks down into N-14. So, it will be less C-14 and C-12 will remain the same. The ratio of C-14 to C-12 must decrease over time.
Answer: Surface water is water located on top of the Earth's surface such as rivers, creeks, and wetlands. This may also be referred to as blue water. The vast majority is produced by precipitation and water runoff from nearby areas.
Explanation:
Answer:

✏ Arteries are the vessels that carry blood away from the heart to various organs of the body.Since, the blood emerges from the heart under high pressure, the arteries have thick, elastic walls.