Express the density of mecury in lb/ft³

Type the letter that represents the correct location for each particle type below.

What is the polyatamic ion of borate

The bond energy for the van der waals bond between two helium atoms is 7.9×10−4ev. assuming that the average kinetic energy of a helium atom is (3/2)kbt, at what temperature is the average kinetic energy equal to the bond energy between two helium atoms