Well, D is definitely correct - t<span>hey both share cultures, especially along the border, because they used to be one country in the past.
I'm not sure about the second answer though, perhaps C (</span><span>They both work together as economic partners.) is correct because they do trade a lot. </span>
The correct answer is - ozone.
The ozone is essentially three molecules of oxygen, or O³. This gas is crucial for the life on the Earth because it is the one that manages to filter out big portion of the UV radiation from the Sun which is extremely harmful if its too strong, as it will contribute to the dying out of pretty much every living organism.
While the ozone layer in the stratosphere is very useful, the ozone in the lower parts of the troposphere is actually considered as pollutant. The reason why it is considered as pollutant is because it is very harmful if inhaled, and it also heavily damages the plants.
Answer: See explanation.
Explanation:
Because Astronomers have well-tested theoretical models that explain how a star evolves over the course of its life as well as well-tested theoretical models that explain how a star evolves over the course of its life.
