## Non-native arithmetic using Plonky3

Use the [plonky3](https://github.com/Plonky3/Plonky3) library to create a circuit that performs addition and multiplication operations on the BN254 base field. A Prover should be able to use the circuit to convince a Verifier that he knows some (secret) base field elements $A$ and $B$ and public base field elements $C$ and $D$, such that $A + B = C$ and $A * B = D$.

- The implementation should be "from scratch" (not using existing code for non-native field operations in-circuit).
- The circuit must use a scalar field that is implemented in the repository above.

Partial solutions are acceptable.
You may be asked to explain your code in a follow-up interview.