Some type of path is necessary to join both half-cells in order for electron flow to occur.

true

false

That is true - you have to complete the circuit for that to be done

 Ture: Yes, half cells have to be joined together in order for current to flow, and the salt bridge ensures that ion concentrations remain balanced.

Vander waals forces are inter molecular bonds that exist within molecules of the same substance. a water molecule is made up of oxygen and hydrogen atoms which share electrons between each other. the vander waals forces are forces that exist between multitude of different  molecules of water. dipole dipole forces is the type of vander waals force that exist in water. the oxygen atom which is more electronegative pulls the shared electron closer to itself thus generating a partial negative charge while the hydrogen acquire a partial positive charge. these two different charges causes attraction to occur in water molecules.

Ithink it's the third answer