Problem: Mrs. Carpenter is a teacher. She has a student, Amber, with severe allergies to tree nuts. Students are advised to not bring tree nuts in their lunches. Joe, a student in the class, doesn't pay much attention and brings pistachio cookies to class. He shares one with Amber because he has a crush on her. Amber goes into anaphylactic shock. Plasma proteins are flowing from her blood vessels to the interstitial fluid. Edema is quickly occurring. Which bulk flow pressure is being altered as this is happening?