• Factors Governing Air-Screen Grain Cleaner Capacity:
• An air-screen grain cleaner separates impurities based on aerodynamic drag (aspirator air duct) and particle dimensions (screens):
• Grain bed depth: Governs screen stratification and air passage.
• Size of screen surface: Width and length define total active screening area ($m^2$).
• Feeding mechanism: Ensures uniform, non-pulsing curtain flow across the full screen width.
• Percentage opening area of screen: Dictates open perforation fraction through which clean grain passes.
• Conclusion: Capacity depends on (A), (B), (C) and (D) (Option 3).

Correct option: (3) (A), (B), (C) and (D).

Matching the items of List I with List II for Water gains and water losses from soil:

The correct combination is Option 2: (A) - (Il), (B) - (IV), (C) - (III), (B) - (1).

Correct option: (2) (A) - (Il), (B) - (IV), (C) - (III), (B) - (1)