Sentence 1: Julie was listening to music while browsing the internet. 
 Sentence 3: She had knocked over her speakers and they crashed to the ground 
 Sentence 4:  She picked them up and hoped they would work 
 Sentence 5:  Unfortunately, they seemed officially broken 
 Option 1: She was stretching her arms when she hit something. 
 Option 2: Wearing her headphones she stretched her arms and she hit something.