What is a fundamental physical quantity? name three fundamental physical quantities and for each, give its s. i. units and its u. s. customary units.

meter, second and kilogram

Explanation:

The fundamental quantities in mechanics are: length, mass and time.

In the international system of measurements the unit of length is the meter, in USA the length uses the English system that is the inch

Time is the second unit of measurement in both the SI system and the English system (USA)

The mass has the unit in the system if the kilogram (kg) in the SI system, but the equivalent unit in the groin system is not widely used, they prefer to use the pound even when it is a unit of weight.

which statement about this sum is true? −245+2.7

bacteria that live on the ocean floor are sustained by phytoplankton. phytoplankton, microscopic marine photosynthetic organisms, have a vastly significant role to play not only in the marine food web of which they’re part of, but also on a more global scale. despite their infinitely small size in comparison to other marine organisms, these tiny creatures occupy an immensely important ecological niche: they are the foundation of the marine food web, and as primary producers, play key roles in supporting all other organisms in the marine environment, as well as in the regulation of the earth’s climate through the sequestration of carbon, oxygen production, and other related processes. phytoplankton account for roughly half of all global primary productivity; therefore, their significance extends far beyond the marine environment alone. there is an intriguing sense of irony in the realization that these tiny living beings that often live out their existence unnoticed and undetected by the rest of the world, have such a far-reaching impact on the lives of virtually all other living organisms on the planet, particularly on those in the marine environment. the world that we have become accustomed to has been and is continuously shaped by the workings of these miniscule yet vital “plants of the sea”.

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