O lentila biconvexa simetrica din sticla , avand indicele de refractie n=1,5 , cu distanta focala f=60cm , formeaza imaginea unui obiect asezat la 90cm de ea. Sa se precizeze unde se formeaza imaginea, natura acesteia , marimea liniara transversala. sa se calculeze convergenta lentilei si raza acesteia.

it is the most commonly accepted one

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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~ trueboss72