Which of the following would increase density? increase mass and volume by the same amount decrease mass and volume by the same amount increase mass, but keep volume the same decrease mass, but keep volume the same

answer; i believe the answer is hydraulic action;

step 1: nitrogen fixation- conversion of atmospheric no₂ into forms useful to plants by lightning, bacteria, and cyanobacteria.

step 2: nitrification-process of converting ammonia to nitrite or nitrate.

step 3: assimilation-plant roots absorb new form of nitrogen.

step 4: ammonification-conversion of organic nitrogen to ammonia by bacteria involved in decomposition.

step 5: denitrification-bacteria turns the decomposed matter back into n₂o, which is released into atmosphere; repeat cycle.

it is a limiting nutrient limited by a single nutrient in the ecosystem, & the single goes very slow.