Answer: There are several information's already given in the question. It will be easier to get the answer, if we write all the details down first.
AB = 13200 miles
AO = 4000 miles
OB = 4000 miles
Let us assume CB = x
Then
(x + 4000)^2 = (13200)^2 + (4000)^2
x = sqrt(13200^2 + 4000^2) - 4000
= 13793 - 4000
= 9793 miles.
From the above deduction, it can be concluded that the correct option among all the options that are given in the question is the third option.
