A. contains 23% N, 19 % K, 17 % P

B. contains 23% N, 19 % K₂O, 17 % P₂O₅                        

C. provides 23 % of P, 19 % of K, and 17 % of plant N needs

D. none of these

A. Dissolution of occluded P

B. Hydrolysis of Fe phosphate

C. Increase mineralization of organic P in acid soils

D. All the above

A. ZnNO₃

B. ZnCO₃

C. ZnSO₄

D. ZnCl₂

A. High pH soils

B. calcareous soils

C. low pH soils

D. both A and B

A. Fe

B. C

C. O2

D. all of the above

A. EDTA                                 

B. EBT

C. AgNO₃

D. KCrO₄

A. 80:1

B. 60:1

C. 40:1

D. 20:1

A. Mineralization

B. Immobilization

C. Nitrification

D. Denitrification

A. NO₃            

B. OH^–

C. H⁺

D. H₂O

A. Salinity  

B. Alkalinity

C. Sodicity

D. Acidity