🔍 Key Concepts

• Centrifuge bowl internals – identify which parts are structural (metal components) vs. flow paths or abstract ‘zones’. • In a fuel purifier, the disc stack increases the effective settling area between light and heavy phases. • Distinguish between a physical object (like plates or discs) and an operating characteristic (like angle, direction, or relative size of a separation zone).

💭 Think About

• Look closely at where label "N" touches the illustration: is it pointing to a space/angle, a direction arrow, or a set of solid metal parts? • Ask yourself what feature in a purifier actually creates many thin layers to speed up separation of heavy and light phases. • Which answer choices describe something you can physically touch in the cross‑section, and which describe how the purifier behaves during operation?

✅ Before You Answer

• Verify whether "N" is indicating a group of thin conical components arranged on the bowl spindle, or an empty region/zone between them. • Check if there are any arrows or shaded regions that might instead represent flow direction or separation zones – is "N" tied to those, or to a solid object? • Confirm that your choice matches a specific, visible part labeled by the arrow, not a general concept that isn’t directly drawn in the picture.