Answer:
Vacuum
Explanation:
A vacuum is usually defined as a space in which there is an absence of matter. It can also be said that there is an extremely low amount of pressure due to which the particles present in it are not affected by any type of process that occurs in space. The value of pressure is lower than the value of normal atmospheric pressure.
For example, sound cannot travel in space because there is no medium such as water and air through which the sound waves can propagate.
When Amanda poured some of the liquid in a test tube, she noticed that the edges of the water curved upward, which is an example of adhesion.
When Pol filled another test tube to the top, the liquid formed a low dome, which is evidence of cohesion.
When Amanda added table salt to the first test tube and shook it, she noted that the liquid had dissolved the solute.
All of these observations indicated the presence of covalent bonds.
Pol determined that the pH of the sample is 7, which shows the sample is neutral.
Based on all of the evidence Amanda and Pol gathered, the unknown liquid is water.
The carbon cycles recycles caronatoms(carbon dioxide) and the nitrogen cycle recycles nitrogen.and the carbon cycle makes carbon dioxide and the carbon dioxide goes to the trees ,and the trees get the nitrogen and starts the cycle again.
The first one according to the graph
