👨‍💼 Our developers are having a hard time using the Calculator component properly, so I want you to add type annotations.

I'd also like you to meet Lily the Life Jacket! 🦺 She's going to be hanging around with the rest of the crew to indicate wherever there's something that's TypeScript-specific you need to do and to give you TypeScript-specific tips. You'll be working with Lily the Life Jacket a lot in this exercise.

Follow the emoji!