Final answer:
The number of Boundary Layer Energizers per wing varies based on the aircraft design and requirements, but typically 2 to 4 are used in general aviation.
Step-by-step explanation:
The number of Boundary Layer Energizers per wing depends on the specific design and requirements of the aircraft. However, in general aviation, it is common to have 2 to 4 Boundary Layer Energizers per wing. These energizers are used to reduce drag and improve the performance of the aircraft by energizing the boundary layer, which is the layer of air that flows over the surface of the wing.