An observer sees an airplane flying directly overhead and determines that the distance from the wingtip to wingtip subtends and angle of 0.0080...

An observer sees an airplane flying directly overhead and determines that the distance from the wingtip to wingtip subtends and angle of 0.0080 radians. She knows that the wingspan of the airplane is actually 160 feet. What is its altitude?

a) 10,000 ft

b) 15,000 ft

c) 20,000 ft

d) 25,000 ft