Question

1. check all that apply.

what are four innovations in farming techniques that led to great productivity?
gas - powered thresher
disease control
flood - resistant seed
crop rotation
contour plowing
drought - resistant seed
underground plowing

Explanation:

To determine the four innovations in farming techniques that led to great productivity, we analyze each option:

• gas - powered thresher: Mechanizes threshing, increasing efficiency.
• crop rotation: Improves soil fertility and reduces pests/diseases, boosting yields.
• contour plowing: Prevents soil erosion, maintaining soil quality for better productivity.
• drought - resistant seed: Allows crops to survive dry conditions, ensuring production.

"Disease control" is more of a general agricultural practice, "flood - resistant seed" is less commonly a key historical innovation for great productivity compared to the others, and "underground plowing" is not a standard productive farming technique.

Answer:

• gas - powered thresher
• crop rotation
• contour plowing
• drought - resistant seed