The mass of piece of sterling silver jewelry is 33.24 g. It contains 92.5% silver Ag by mass. Since, sterling silver is an alloy of Ag-Cu thus, percentage of Cu will be:
% Cu=100-92.5=7.5%
Thus, mass of copper will be:

Molar mass of Cu is 63.546 g/mol, thus, number of moles of Cu can be calculated as follows:

Here, m is mass and M is molar mass.
Putting the values,

Now, in 1 mole of Cu there are
thus, in 0.03923 mol, number of Cu atoms will be:

Thus, number of atoms of Cu will be
.
Answer:
well they form by heat and pressure
At 4 °C, the clusters start forming. The molecules are still slowing down and coming closer together, but the formation of clusters makes the molecules be further apart. Thus, the density of water is a maximum at 4 °C.
Answer:
Explanation:
By moving weather systems quickly
I think this is correct