AviationTire General Navigation Dead Reckoning Navigation (Dr) Calculate DR elements Q 5 / 5

Given: Aircraft at FL 150 overhead an airport Elevation of airport 720 FT. QNH is 1003 hPa. OAT at FL150 -5° C.
What is the true altitude of the aircraft? (Assume 1 hPa = 27 FT)

15 840 FT
15 280 FT
14 160 FT
14 720 FT