The buildup of waste products in muscle cells that are active might cause
(1) digestion (3) increased fatigue
(2) cellular respiration (4) decreased heart rate

poor water quality affects most estuarine organisms, including commercially important fish and shellfish. the pollutants that have the greatest impact on the health of estuaries include toxic substances like chemicals and heavy metals, nutrient pollution (or eutrophication), and pathogens such as bacteria or viruses.

i was thinking 4.0 v hope this