Judging by the density (19.3 g/ml) there's a very good chance that it could be gold.
The graph is missing, however we can answer anyway.
In fact, this is the approximate percentage of the elements listed in the questions in the Earth's crust (data taken from wikipedia):
Iron 5.0 %
Calcium 3.6 %
Sodium 2.8 %
Potassium 2.6 %
Magnesium 1.5 %
of all of these, we see that the combination of two elements that makes up the closest number to 7% is calcium and sodium (3.6% + 2.8%=6.4%), therefore the correct answer is
Calcium and sodium.
Answer:
the answer is B
Explanation:
the law states that for every action there is an equal and opposite reaction. action and reaction forces always act on two two different bodies and therefore THEY ALWAYS EXIST IN PAIRS.

Explanation:
At the top of the tree, the velocity of the pebble is purely horizontal so we can calculate it as


The atom that is the most electronegative is fluorine (F).
<h3>
What is electronegative?</h3>
Electronegativity, is the tendency for an atom of a given chemical element to attract shared electrons when forming a chemical bond.
Electronegativity increases across the groups from left to right of the periodic table and decreases down the group.
Examples of electronegative elements arranged in decreasing order;
- fluorine,
- oxygen,
- nitrogen,
- chlorine,
- bromine,
- iodine,
- sulfur,
- carbon, and
- hydrogen.
Thus, the atom that is the most electronegative is fluorine (F).
Learn more about electronegativity here: brainly.com/question/24977425
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