Category: Soil Science

A. Native element
B. Secondary element
C. Primary element
D. Heavy metal

A. Sand stone
B. Classics
C. Igneous
D. Greis

A. Alkaline
B. Neutral
C. Acidic
D. None of the above

A. Granulation
B. Tillage
C. Tilth
D. All the above

A. Nickle
B. Natrium
C. Neon
D. None of these

A. Vonliebig
B. Neil Brady
C. Neuron
D. J. jones

A. Ziebig
B. Newton
C. Neil
D. Jenny