"Sound is a form of energy that travels through a medium in the form of waves. These waves are produced by vibrating objects and can travel through gases, liquids, and solids. The speed of sound varies depending on the medium it travels through, being fastest in _______ , slower in _______ , and slowest in _______. This variation is due to the differences in the molecular structure of these mediums. In solids, the molecules are _______ packed, which allows sound waves to transmit quickly. In contrast, gases have molecules that are spread apart, making it more challenging for sound to travel quickly."
Fill in the blanks:
1
liquids, solids, gases, loosely
2
solids, liquids, gases, closely
3
gases, liquids, solids, tightly
4
solids, gases, liquids, loosely