D. Protons, Atomic number is the number of protons in an atom.
If the concentration of water inside a cell is higher than the concentration of water outside a cell, osmosis will take place, as water will move from an area of low solute concentration inside the cell to higher solute concentration, outside the cell.
Answer:
(a) 
(b)


(c) 
Explanation:
Hello,
(a) In this case, with the given formula we easily compute the mass of gold contained in the sovereign as shown below:

(b) Now, by knowing the density of gold and copper, 19.32 and 8.94 g/cm³ respectively, we compute each volume, by also knowing that the rest of the coin contains copper:


(c) Finally, the volume is computed by dividing the total mass over the total volume containing both gold and copper:

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