17. What implement drawn by domesticated farm animals to tilt the land? A. Harrow C. disc harrow B. Plow D. disc plow 18. It is used to tilt the land. How do you call it? A. Garden hoe B. Shovel C. harrow D. plow 19. An implement attached to a four-wheel tractor used to pulverize the soil. What is it? A. Native harrow C. bamboo harrow D. Wooden harrow B. Disc harrow 20. Bacteria, viruses, molds, mildew are examples of what hazards? C. biological D. Ergonomic A. Physical hazard B. Chemical Hazzard​