Answer:
They accurately compare the current atmosphere with the previous one, by assessing the amount of atmospheric gases present today, with the amount of atmospheric gases trapped in ice cores that they believe are millennial, that is, they have existed for thousands of years ago.
Explanation:
As we know, it is difficult to compare current characteristics of the planet earth with characteristics that the planet had in the past, thousands of years ago. This is because the ancient characteristics on earth are not fully available to be analyzed, since most of them have been modified over time.
To do this, scientists need to find factors that may have existed thousands of years ago and assess whether these factors have any account of the characteristics of the earth. In the case of atmospheric characteristics, it is common for scientists to compare the current atmosphere with the atmosphere of thousands of years ago, with the assessment of the amount of atmospheric gases trapped in ancient ice cores, with the amount of atmospheric gases present in the atmosphere today.
A.The way plant pollen is carried by wind to another plant.
In a typical ECG (Electrocardiogram) the first wave obtained is P wave; The P wave represents the depolarization of the atria. After this, the QRS complex is formed. The QRS wave represents the depolarization of the ventricles. During the depolarization phase, the ventricles contracts and pushes the blood into the atria. Hence, the correct answer is depolarization of the ventricles.
