Decaying plant matter
Decaying animal matter
Nutrients such as nitrogen, and biological activity
Planting cover crops when corn or wheat is harvested from the fields.
Adding cow, horse, or chicken manure and turning it under in the spring
Composting food scraps, egg shells, leaves and coffee grounds and adding to the soil before you plow.
The type of vegetation
All answers are correct
Type of humus
A steep slope in a warm, wet climate
A flat area in a cold, wet climate
A flat area in a warm, wet climate
About the same