I think that the answer is D
As far as I remember, a triangle equals 180 degrees. 31+35=66. 180-66=114. 114/38=3. So b=3.
Over its sixty-year lifetime, the B-52’s avionics, flight hardware, and weapons systems have been upgraded. In 2006, the fleet received a “mid-life” upgrade to its avionics, adding modern processors and navigation systems. In 2014, the Air Force gave the BUFFS their first new communications system since the 1960s, including full-color LCDs to replace the old cathode ray tube screens. <span>On the weapons front, the airplanes are due to receive weapons-bay upgrades, enabling them to hold more smart bombs, and radar enhancements, potentially including the Active Electronically Scanned Array Systems technology. Used by fighter jets like the F-22 Raptor, the digital radar system is vastly more precise and offers higher resolution than conventional radar dishes. </span>