Which of the following could not act as a medium for a mechanical wave? a) air
b) empty space
c) liquid water
d) a solid rope

b) empty space

Explanation:

A mechanical cannot travel through empty space. So option (b) is correct.

A mechanical wave is a wave which needs a material medium for its propagation. For example sound, water waves etc . The medium required by the wave can be a solid, liquid or a gas. Empty space doesn't have any medium, so a mechanical wave cannot travel through empty space.

b..

is the correct one

explanation:

covalent bonds form as valence electrons are shared between two atoms. lewis structures and structural formulas are common ways of showing the covalent bonding in organic molecules. formal charge describes the changes in the number of valence electrons as an atom becomes bonded into a molecule.

2b2t

explanation:

2b2t