Hopeful
Feeling
Base
Brass
Hope this helps you
I'm not 100% sure. but I believe it's the third option
"She bought the least expensive cage for George, the parakeet."
What proof of his love does Juliet ask from Romeo?
An omen suggesting a tragic end to the battle
Books that are surrounded by oxygen will turn yellow, so basically, all books since oxygen is constantly surrounding us. Oxygen-rich conditions are very bad for paper, which gives them the yellow tiny. This is actually called lignin oxidation! Lignin oxidation gives it a yellow or brown colour as you said. Yellow comes first, then brown after.
I hope this helped a bit! :)