Concave is not a type of mechanical wave because it doesn’t need a medium for propagation.
Answer:
=8 atoms
Explanation:
In (NH4)2C2O4 there are four moles of Hydrogen in the compound (NH4), but there two molecules of (NH4) in this compound. That's what the 2 in (NH4)2 means, so multiply 4 x 2 = 8.
Hope this helps (:
It is elastic potential energy
