What is the average atomic mass of 38 atoms of Copper-65 and 92 atoms of Copper-63?

Copper has two naturally occurring isotopes, ${ }^{6} \mathrm{Cu}$ (isotopic mass $=62.9296 \mathrm{amu}$ ) and ${ }^{65} \mathrm{Cu}$ (isotopic mass $=64.9278$ amu . If copper has an atomic mass of 63.546 amu, what is the percent abundance of each isotope?

It will fall off and tip over. 

The activity series is shown in the attached picture. if the element is below the other, then you can displace the other. following the activity series as a guide, the reactions are as follows: nickel and aluminum chloride3 ni + 2 alcl₃  → 3 nicl₂ + 2 albarium and copper bromideba + cubr  →  no reaction because cu is less oxidizable than bapotassium nitrate and aluminum3 kno₃ + al  → al(no₃)₃ + 3 ksodium phosphate and zincnaso₄ + zn  → znso₄ + na