Write a proportion for each pair of ratios that are equivalent.
a) 2:3, 6:9 b) 5:2, 15:6
c) 4:8, 2:1 d) 12:15, 4:5
e) 18:9, 3:6 f) 6:12, 5:10

Need ! a certain ultraviolet ray has a frequency of 1 × 1016 hz, and a certain infrared ray has a frequency of 2 × 1012 hz. which of the following is true? a. the frequency of the ultraviolet ray is fifty thousand times the frequency of the infrared ray. b. the frequency of the infrared ray is fifty thousand times the frequency of the ultraviolet ray. c. the frequency of the ultraviolet ray is five thousand times the frequency of the infrared ray. d. the frequency of the infrared ray is five thousand times the frequency of the ultraviolet ray.