Which of the following is an example of positive feedback in the lumen of the stomach?
- chief cells secrete pepsinogen, which is a precursor to pepsin.
- pepsin digests molecules of pepsinogen, producing more pepsin.
- pepsin works best in the acidic environment produced by hydrochloric acid.
- hydrochloric acid converts pepsinogen to pepsin.

Sean is getting frustrated by his math homework. rebecca sean with his math homework. in a neutral tone, rebecca explains to sean how to solve the equation he was having difficulty with. sean is impressed by rebecca’s mathematical mastery. later, he describes her as warm and friendly. based on the information above and sean’s question, what might a psychologist conclude about his social perception? a. sean’s opinion about rebecca’s friendliness was part of a conscious desire to overlook her cold behavior. b. sean’s opinion about rebecca’s friendliness was influenced by his own positive mood and feelings. c. sean’s opinion about rebecca’s friendliness was based on interactions with other math students. d. sean’s opinion about rebecca’s friendliness was affected by his positive assessment of her math skills.