They provide oxygen
They provide shelter for animals
Answer:
The Contralto is the lowest female singing voice and like the Basses and Countertenors, they're quite rare. The Contralto has a tessitura of around an E3-E5 and a good amount of vocal weight. These are the ladies that almost sound like men when they speak or sing lower notes.
Explanation:
The answer is (a) Mesozoic and it lasted 180 million years.
