Final answer:
The question is about the limitations on the use of an APU in terms of APU starts and cooling time for the APU starter.
Step-by-step explanation:
The subject of this question is Computers and Technology and the grade level is High School.
The question is asking about the limitations on the use of an Auxiliary Power Unit (APU) in terms of the number of APU starts and the cooling time for the APU starter. The answer to the question can be found in the given reference information. According to the information, there is a limit on the number of APU starts within a specific time period for APU starter cooling, but the exact number is not mentioned.
In conclusion, the question is related to the limitations on the use of an APU, specifically in terms of the number of APU starts and cooling time for the APU starter.