Author Question: When only synthetic fertilizers are used on a crop, the quantity used needs to be increased over ... (Read 61 times)

james0929 · **on:** Aug 27, 2018

When only synthetic fertilizers are used on a crop, the quantity used needs to be increased over time because ________.

A) they are washed away by seasonal rains, but residual fertilizers remain
B) organisms in the soil develop a resistance to these fertilizers
C) more and more genetically engineered crops are being planted
D) synthetic fertilizers provide no organic bulk

Question 2

Ozone, O3, is ________.

A) a pollutant
B) a naturally occurring compound
C) an elemental material
D) all of the above