Respuesta :

∠BFG is an interior angle, then:
m∠BFG=[m arc(GB) + m arc(CD)] / 2
Answer: First option 

Answer: First option is correct.

Step-by-step explanation:

Using the inscribed angle theorem, which states that the angle inscribed at the center is half of the sum of measure of its intercepted arcs.

So, m∠BFG is the inscribed angle.

And its intercepted arcs are BG and CD.

So, According to theorem,

[tex]m\angle BFG=\frac{GB+CD}{2}[/tex]

Hence, First option is correct.