Era is used to mark the boundaries of geological time scale by using radio carbon dating technique.
Explanation:
Geological time starts with Precambrian time.
Geologically, time is divided between the Precambrian era and present time into era.
The three eras are Paleozoic era, Triassic period and Cenozoic era.
Era is further divided into periods.
Scientists use radio carbon dating to study fossils and rock formation. With this study they were able to divide them in exact geological scale.
Geologic scale is the record of events in earth's history and evolution.
A (m) is likely to be smallest
The order in which toxic nitrogen compounds are converted to less toxic nitrogen compounds in the nitrogen cycle is NH3 ----> NO2- -----> NO3-
The nitrogen cycle refers to the movement of nitrogen in the ecosystem. The process of converting nitrogen into less toxic forms of nitrogen which is useful to plants is called nitrification.
During the process of nitrification, ammonia or ammonium is first converted to nitrates by the action of the microorganism called nitrosomonas. Nitrobacter converts nitrites to nitrates which are useful to plants.
Hence, the order in which toxic nitrogen compounds are converted to less toxic nitrogen compounds in the nitrogen cycle is NH3 ----> NO2- -----> NO3-
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<span>it can form four covalent bonds it forms very strong bonds
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A series of radiographic images taken of the stomach and duodenum after the contrast agent barium has been swallowed is an upper GI series, where
GI<span> stands for "</span>gastrointestinal<span>," which means "stomach and intestines".
</span>This x-ray examination of the upper gastrointestinal<span> (</span>GI<span>) tract,</span>can diagnose problems in your upper GI tract, how to prepare for the procedure, and what to expect afterwards.
