The correct statements are:

a) Solids have definite shape and volume.

d) Liquids do not have a definite shape but have a definite volume.

Explanation:

a) Solids have definite shape and volume: This statement is correct. Solids are characterized by their strong intermolecular forces, which hold their particles tightly together in a fixed arrangement. As a result, solids maintain a definite shape and volume.

b) Liquids have definite shape and volume: This statement is incorrect. Liquids, unlike solids, do not have a definite shape. They take the shape of the container they are placed in. However, they do have a definite volume since their particles are still close together, but not as tightly packed as in a solid.

c) Solids do not have a definite shape but have a definite volume: This statement is incorrect. As mentioned earlier, solids do have a definite shape. The arrangement of particles in a solid remains fixed, giving it a specific shape.

d) Liquids do not have a definite shape but have a definite volume: This statement is correct. Liquids, unlike solids, do not have a definite shape. They take the shape of their container, allowing them to flow and adapt to its shape. However, like solids, liquids have a definite volume as their particles are still close together, albeit more loosely than in a solid.

In summary, solids have a definite shape and volume, while liquids do not have a definite shape but have a definite volume.