Final answer:
The correct answer is (b) Three; two, as most commercial aircraft have multiple weight-on-wheels sensors on the main gear and at least one on the nose gear for detecting the aircraft's weight for safe operation.
Step-by-step explanation:
The number of weight-on-wheels (WOW) sensors on an aircraft's landing gear is typically determined by the design and requirements of the specific aircraft. However, for this question, the correct answer would be choice (b) Three; two. Most commercial aircraft have multiple WOW sensors on the main landing gear and at least one sensor on the nose gear to accurately detect the presence of the aircraft's weight on the wheels, which is important for various aircraft systems such as landing gear retraction, spoiler deployment, and braking systems.
To further explain, the difference between 1 and 2 units of weight is more likely detectable than a difference between 2 and 4 units. This highlights the necessity for precision in the functioning of sensors like the WOW sensors, where accurate detection is crucial for the safety and operation of the aircraft.