Answer:
1) Reflective
"I am brave too," thought Cornelia.
Cornelia strikes me as incredibly clever based on the facts provided by the narrator. As a result, she is an "overthinker" who is very contemplative. Her uncertainties and confidence arise from her ideas, which influence how she sees herself. Furthermore, her self-image is often founded on her appraisal of her previous behaviors (or experience). For example, when she thinks back on her performance in a class play, she remembers how she "had learned all her lines backwards and forwards, and at the end of the performance the audience had responded with thunder." Her accomplishment in the performance gives her confidence that she will deliver her speech successfully as well.
Cornelia's reflective character is further shown when the narrator discloses her internal conversation with herself, in which she questions whether the notion she has of herself as an impostor is accurate. She wonders whether she is "fair to herself." Then she reminds herself that running for student council secretary was her own idea and effort. Cornelia's reflective character is the root of her ideas, behaviors, and self-identity, despite the fact that she may be classified as skeptical or even adventurous (for being eager to try new things and risk failure).