Answer:
C. both
Explanation:
The particle theory and wave theory are both used today.
The particle theory tells us that light is a particle or photon. The wave theory tells us that light travels in waves.
Answer: Several types of evidence supported Hess's theory of sea-floor spreading: eruptions of molten material, magnetic stripes in the rock of the ocean floor, and the ages of the rocks themselves. This evidence led scientists to look again at Wegener's hypothesis of continental drift.
Explanation:
