Why are the current borders of the Middle East different than the ones agreed upon by European countries after World War I?

Belgium and the Netherlands swap land near Lanaye and Oost-Maarland over the discovery of a headless body several years prior, which the Belgian Authorities could not access without crossing Dutch territory. The border has been straightened out and now runs down the center of the Meuse River.[5] The change took effect on 1 January 2018.

Explanation:

the correct option is c.

isotopes refers to different forms of the same element with the same atomic number but different mass number as a result of difference in their neutron numbers. isotopes have different relative atomic mass but share the same chemical properties.

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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