When the temperature of the air becomes almost equal to the dew point the air becomes saturated and the relative humidity during this condition becomes 100%. If the temperature of the air decrease below the dew point the relative humidity will be 100% or exceeds 100%. This condition, when the temperature of the air decreases below the dew point is called supersaturation but most of the time the temperature of the air will be lower than the dew point.
Answer:
Scientist 1
Explanation:
<em>The conclusion of scientists 1 is valid.</em>
Human activities such as burning of fossil fuels, agriculture, deforestation, etc. leads to the emission of carbon in the form of carbon dioxide into the atmosphere. <em>An increase in the population of a city will only lead to an increase in these activities and hence, an increase in the amount of carbon emitted into the atmosphere.</em>
Also, volcanic activities leads to the production of volcanic gases which is a mixture of carbon dioxide, oxides of sulfur, nitrogen, etc.
<u>However, an active volcano that is several miles away from the city might not be a major source of carbon in the air above a large city. The carbon dioxide produced from such volcanic activity thins out before reaching the city.</u>
Answer:
In addition to biology, evidence drawn from many different disciplines, including chemistry, geology, and mathematics, supports models of the origin of life on Earth. In order to determine when the first forms of life likely formed, the rate of radioactive decay can be used to determine the age of the oldest rocks (see optional problems C and D, below) exposed on Earth’s surface. These are found to be approximately 3.5 billion years old. The age of rocks can be correlated to fossils of the earliest forms of life. A. The graph compares times of divergence from the last common ancestor based on the fossil record with a "molecular time" constructed by comparing sequences of conserved proteins to determine a mutation rate (after Hedges and Kumar, Trends in Genetics, 2003). Explain how such a molecular clock could be refined to infer time or the evolution of prokaryotes. B. Using a molecular clock constructed from 32 conserved proteins, Hedges and colleagues (Battistuzzi et al., BMC Evol. Biol. 2004) estimated the times during which key biological processes evolved. A diagram based on their work is shown. Connect the time of the origin of life inferred from this diagram with the age of the oldest fossil stromatolites and the age of the oldest exposed rock to show how evidence from different scientific disciplines provides support for the concept of evolution. Evaluate the legitimacy of claims drawn from these different disciplines (biology, geology, and mathematics) regarding the origin of life on Earth. The oldest known rocks are exposed at three locations: Greenland, Australia, and Swaziland. The following application of mathematical methods provides essential evidence of the minimum age of Earth.
Explanation:
The Precambrian era envelopes the major bulk of the history of the Earth, beginning from the creation of the planet approx 4.5 billion years ago and terminating with the origination of composite, multicelled forms of life approximately 4 billion years after.
The Precambrian refers to the earliest of the geologic ages that are signified by the distinct layers of sedimentary rock. The Earth was about more than six hundred million years old when life started. The planet had cooled down from its native molten state, creating a solid crust and oceans formed by water vapor in the atmosphere.
At about three billion years ago, the atmosphere of the Earth was virtually devoid of oxygen. At approximately 2.4 billion years ago, oxygen was discharged from the seas as a waste product of photosynthesis by cyanobacteria. The levels of the gas slowly raised, attaining about 1 percent around two billion years ago.
Approximately 800 million years ago, the levels of oxygen attained about 21 percent and started to breathe life into more composite species. The oxygen-rich ozone layer was also created, protecting the surface of the Earth from the harmful solar radiation.
