Your sister wants to participate in the yearly science fair at her high school and asks you to suggest some exciting project. You suggest that she experiment with your recently created electron extractor to suspend her cat in the air. You tell her to buy a copper plate and bolt it to the ceiling in her room and then use your electron extractor to transfer electrons from the plate to the cat. If the cat weighs 6.67 kg and is suspended 1.73 m below the ceiling, how many electrons have to be extracted from the cat? Assume that the cat and the metal plate are point charges.