Complementary colours are colours that are combined to make a grayscale off colours
A complementary pair is when you combine colours that are opposite of each other like red and green, or yellow and purple etc.
When you put two of these colours together they cancel each other out which leads to that grayscale of colours like grey or even brown
For title as a brick wall
First one: It would be on Sol
Second one: No. It would be on La. The note is B. And is a Bflat
(I don't know Bass Clef as well. I play Alto Sax, which uses Treble Clef. So please forgive me)
Third one: It would be A flat
Fourth one: It would be C then C flat
(Again, I don't know Bass Clef that well, so don't count on my answers)
