The answer is C. 3 meters per second (m/s)
Hopes this helps and if you can can you give me brainiest
Answer:

Explanation:
By using relation,
Speed of light = frequency × wavelength (in m)
Can a measurement be exact? No
Answer:
BaF2
Explanation:
since you got the valence numbers just do the scissors move where you:
give the F the 2 and give the Ba the 1 so it be like
BaF2 here is the chemical compound