Sentence 1: Kayla has a science test in the morning. 
 Sentence 3: When she went to class the next day, she felt ready 
 Sentence 4:  She turned in her test in record time 
 Sentence 5:  When the grades were posted, she made a perfect score 
 Option 1: She was worried about making a bad grade so studied all night. 
 Option 2: She was worried about making a bad grade since she had failed to study at all.