Answer:
✔️But even our commercial policy should hold an equal and impartial hand; neither seeking nor granting exclusive favors and preferences.
Step-by-step explanation:
The excerpt that best supports George Washington's belief that the U.S. should deal cautiously in economic affairs is "But even our commercial policy should hold an equal and impartial hand; neither seeking nor granting exclusive favors and preferences."
Washington advices that the U.S should deal cautiously in economic affairs by making sure that commercial and economic policies are impartial and are equitable. He clearly stated that it should be free from bribery and preferential treatment.