Light passes from substance a into substance b as shown. what could these two substances be? a. a could be water (speed of light = 225,000 km/s); b could be air (speed of light = 300,000 km/s). b. a could be water (speed of light = 225,000 km/s); b could be glass (speed of light = 200,000 km/s). c. a could be ruby (speed of light = 170,000 km/s); b could be sapphire (speed of light = 170,000 km/s). d. a could be water (speed of light = 225,000 km/s); b could be diamond (speed of light = 120,000 km/s).