Answer:
This question is incomplete
Step-by-step explanation:
This question is incomplete because there are some parameters that are missing. However, when calculating the average emf and speed/velocity is provided, then
average emf = Brvl
where Br is the vertical component of the earth's magnetic field (in weber per square meter, Wb/m²)
v is velocity (in m/s)
l is the length (in meter) of the wing span