Alona's persistent knocking at the door of room 412 went unanswered for three minutes as she nervously shuffled her feet. Her book bag was super-saturated with textbooks, notebooks, schedules, rough drafts, and various other forms of academic paraphernalia. It was getting heavier. She continued to knock, even though there had as yet been no answer, because the note card tacked to the right of the door indicated that these indeed were Prof. Turgy K. Sigger's office hours. She could see the light under the door and thought she had heard a groan. Just before she decided to give up, slow feet approached from the opposite side, then silence; with a dramatic turn of the knob, the door swung open. "Was this trip really necessary?" asked Prof. Sigger, blinking and brushing his oily, graying hair back into place. "These are your office hours," Alona replied. She nervously smiled, feeling the corners of her mouth twitch. Somewhere in the darkened hall, a janitor coughed. "All right," conceded Prof. Sigger. "Come in." The carpet was smothered by leaning towers of textbooks. Papers lined the left side of the desk, above which was a small note card which read "To Be Graded." On the right side, the oak finish gleamed of the mid-morning light piercing the Venetian blinds. "You've come about your final project," Prof. Sigger stated. "It's only mid-term," Alona reminded him. "Oh yes, yes," continued Prof. Sigger, without conscious embarrassment. "Mid-term grade. I think I have it here. Somewhere." His hands disappeared into the left side of his desk. "You told the class that we would get a C if we maintained that Coca-Cola isn't a crypto-fascist conspiracy." "Oh yes," said Prof. Sigger. "We were discussing social issues, as I remember. I was quoting Marx and some little idiot brought up Rush Limbaugh." "That was me," Alona muttered. According to the above context, answer the following question. What was getting heavier as time went on?
The answer is:
Alona's book bag