John was studying the history of dinosaurs. He found that dinosaurs were flourishing before 66 million years ago. He labeled it as era A. Then he found that there was a mass extinction around 66 million years ago. He labeled that time period as era B. John found it interesting that many species have evolved in the course of history. Which era would less likely be longer, era A or era B? Hint: Species go extinct constantly as environments change, as organisms compete for environmental niches, and as genetic mutation leads to the rise of new species from older ones. Occasionally biodiversity on Earth takes a hit in the form of a mass extinction in which the extinction rate is much higher than usual. A large extinction-event often represents an accumulation of smaller extinction- events that take place in a relatively brief period of time.The first known mass extinction in earth's history was the Great Oxygenation Event 2.4 billion years ago. That event led to the loss of most of the planet's obligate anaerobes. Researchers have identified five major extinction events in earth's history since:
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Answer: era A

Tho towns located on opposite banks of a river, had a humid season, but Bend town had a cooler air at night. Bank town on the other hand, had warmer nights because it was situated on a south facing hill. Which town experienced a lower air temperature? Hint: Specific humidity (or moisture content) is the ratio of the mass of water vapor to the total mass of the moist air parcel.[13] Specific humidity is approximately equal to the mixing ratio, which is defined as the ratio of the mass of water vapor in an air parcel to the mass of dry air for the same parcel. As temperature decreases, the amount of water vapor needed to reach saturation also decreases. As the temperature of a parcel of air becomes lower it will eventually reach the point of saturation without adding or losing water mass.
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Answer: Bend

Barbara and Jane are two students. They both like meteorology. Barbara studies the formation of the ozone layer, while Jane studies about the stratosphere. Which student learned more about (O3) photolysis? Hint: The mechanism describing the formation of the ozone layer was described by British mathematician Sydney Chapman in 1930. Molecular oxygen absorbs high energy sunlight in the UV-C region, at wavelengths shorter than about 240 nm. Radicals produced from the homolytically split oxygen molecules combine with molecular oxygen to form ozone. Ozone in turn is photolysed much more rapidly than molecular oxygen as it has a stronger absorption that occurs at longer wavelengths, where the solar emission is more intense. Ozone (O3) photolysis produces O and O2. The oxygen atom product combines with atmospheric molecular oxygen to reform O3, releasing heat. The rapid photolysis and reformation of ozone heats the stratosphere resulting in a temperature inversion. This increase of temperature with altitude is characteristic of the stratosphere; its resistance to vertical mixing means that it is stratified. Within the stratosphere temperatures increase with altitude (see temperature inversion); the top of the stratosphere has a temperature of about 270 K (3C or 26.6F). This vertical stratification, with warmer layers above and cooler layers below, makes the stratosphere dynamically stable: there is no regular convection and associated turbulence in this part of the atmosphere. However, exceptionally energetic convection processes, such as volcanic eruption columns and overshooting tops in severe supercell thunderstorms, may carry convection into the stratosphere on a very local and temporary basis. Overall the attenuation of solar UV at wavelengths that damage DNA by the ozone layer allows life to exist on the surface of the planet outside of the ocean. All air entering the stratosphere must pass through the tropopause, the temperature minimum that divides the troposphere and stratosphere. The rising air is literally freeze dried; the stratosphere is a very dry place. The top of the stratosphere is called the stratopause, above which the temperature decreases with height.
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Answer:
Barbara