An industrial plant has been discharging effluent into a nearbycreek for a number of years. A local university has been monitoringthe effect of the effluent on the diversity of aquatic organisms inthe stream. Recently, the surveys have shown that the number offish in the creek has fallen significantly. The researchers are nowtrying to find out what has caused this observed increase inmortality. So far, they have discovered that the plant is nowdischarging several new chemicals (X, Y, and Z) in the effluentthat were not previously being disposed of in this way. Theresearchers are now interested in which, if any, of these chemicalsare responsible for fish mortality. They decide to startinvestigating chemical X and set up the following experiment:Experimental Procedure: Four identical aquaria were set up in aroom at 10oC, with 12 hours light, 12 hours dark, all receiving thesame amount of oxygen and food. Different concentrations ofchemical X were added to each tank, as follows: Tank A - 0 mMchemical X Tank B - 5 mM chemical X Tank C - 20 mM chemical X TankD - 100 mM chemical X Each tank then received 10 fish.

The question is:When the researchers carried outthis experiment, they found that chemical X had no significanteffect on fish mortality. What would you suggest that they do next?(paragraph and good explanationneeded to get goodrate