Which of the following is true of liquids and solids? a. liquids have fixed particles and do not expand when heated whereas solids have flowing particles that do expand when heated. b. solids and liquids have a definite shape of tightly packed particles. c. liquids have a definite shape and volume whereas solids have a definite shape but not a definite volume. d. solids have a definite shape and volume whereas liquids have a definite volume but not a definite shape.