Answer:
Leah should ask from Janna before he discusses the idea with his manager.
Explanation:
Leah action is not ethical since it was Janna idea and Leah presented to his manager as if it is his idea. Janna and Leah both are in same industry so if Leah promotes the Janna idea to his manager his company will be more successful than Janna. Leah should have taken permission from Janna before discussing the idea with his manager.