Answer:
18 ATP.
Step-by-step explanation:
Total 18 ATP are produced because 9 FADH2 are converted into 9 ATP molecules and the earlier 9 ATP molecules are already present in the first b-oxidation process. The first Krebs cycle produces 27 NADH, 9 FADH2 and 9 ATP while on the other hand, the second Krebs cycle produces 9 ATP molecules from 9 FADH2 so total it produces 18 ATP molecules.