Answer:
Photograph: bird's eye view of a site; interview: personal analysis and biased; tax records: limited accessibility; biography: unreliability of human memory.
Explanation:
There are generally always some drawbacks when considering different sources of historical information and a good researcher has to take these factors into account. Photographs are limited because they give you very little context. Interviews can be limiting because you get a personal view from just one individual. Tax records are likely protected due to privacy concerns and statutes. Biography can have drawbacks as well because the person may embellish past events or overemphasize the significance or attribute meaning in ways that are not entirely truthful or objective.
The Moons rotation is precisely equal to it’s period of revolution.
Answer:
Iron oxides appeared after the emergence of cyanobacteria.
Explanation:
The composition of Earth's atmosphere in the first couple of billions of years of its existence was nothing like the atmosphere of today. This had a big influence on the processes that were taking place, or rather what processes and to what extent could have happened in those conditions. One big difference between the atmosphere then and after is the levels of oxygen.
Until the appearance of cyanobacteria, the oxygen levels in Earth's atmosphere were very low, and the same goes for the oceans. With a lack of oxygen, the process of oxidation was absent as well. The cyanobacteria though managed to produce oxygen, and this was on such a high scale that they changed the composition of Earth's atmosphere and the oceans. Not just that this enabled complex lifeforms to develop, but it also enabled the process of oxidation. Iron oxides for example occurred only after cyanobacteria appeared, and this can easily be seen when dating the oldest iron oxides and compare that age with the appearance of cyanobacteria.
Answer:
Standards also help support basic consumer protection
by helping to raise levels of quality, safety, reliability, efficiency and interchangeability.
Explanation:
