18. One of the most laborious activity performed during crop farming.
a. Land preparation c. harvesting
b. planting
d. none of these
19. It is used to tilt the land.
a. Garden hoe
b. Shovel c. harrow
d. plow
20. An implement attached to a four-wheel tractor used to pulverize the soil.
a. Native harrow
c. bamboo harrow
b. disc harrow
d. Wooden harrow
21. Bacteria, viruses, molds, mildew are examples of what?
a. Physical hazard
c. biological
b, Chemical Hazzard
d. Ergonomic​