separated some sentences in why we breathe and made a sentence in the amazing heart a non-manipulate sentence
Merge remote-tracking branch 'origin/SarahsBranch' into IntroductionBranch
Added some fixes to the Circulation files, specifically broke down two sentences into four new ones. Added highlighting to the oxygen and the heart in the Why We Breathe vocab intro.
Merge remote-tracking branch 'origin/SarahsBranch' into IntroductionBranch
Fixed the playing of “carbon dioxide”. Added highlighting for the lungs.
Updated the circulatory.epub file.
Fixed the following bugs on the circulatory.epub file:

In Chapter 3, Muscles use Oxygen, the vocabulary word "Arteries" did not play and there was no way to get past it to other vocab words.

There were instances where vocabulary words were not underlined (in particular, carbon dioxide, arteries, and valve).
Updated the metadata file to remove the press next step for blue sentences on the general introduction.
Changed the text to match audio in the best farm chapter 1. Changed text in circulatory chapter 3 via Art’s requests, and therefore had to change the metadata to match...