Answer:
Ytterbium is a chemical element with the symbol Yb and atomic number 70. It is the fourteenth and penultimate element in the lanthanide
I would say B because c and d would decrease competition and a would do the same, or just kill the ecosystem.
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Answer:
Work done, W = 100 J
Explanation:
We have, Billy the friendly Robot uses 50 N of force to lift a box 2 meters in the air.
It is required to find the work done by Billy.
Work done by an object is given in terms of force and displacement. The formula used to find the work done is given by :

So, the work performed by Billy is 100 J.
The haze is called smog, hope this helps, pls mark brainliest!
Answer:
this is your answer
Explanation:
Silicon, like carbon, is relatively inactive at ordinary temperatures; but when heated it reacts vigorously with the halogens (fluorine, chlorine, bromine, and iodine) to form halides and with certain metals to form silicides.
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