write a hypothesis clearly outlining the independent and dependent variables for the following aim of an experiment: To determine the presence of gram-negative bacteria, i.e. faecal coliforms, in water samples collected at six different sampling sites along the Patterson River, by quantifying the concentration of faecal coliforms through conducting the ONPG Test (Colilert Method) and the Most Probable Number (MPN) Test. Moreover, the attainment of these measures will be compared with permissible governmental standards, known as the EPA guidelines, and suitability for primary and secondary recreation contact recreation evaluated.

Context: Turn the following into a 100 word hypothesis: It is hypothesized that if water samples are collected from sites further away (downstream) from the Eastern Sewage Treatment Plant, then those samples will exhibit higher levels of contamination and thus concentration of faecal coliforms. High levels of precipitation across the South-East of Melbourne could have led to sewage spilling into the adjoining Patterson River and as a result the flow of the river may have carried these contaminants downstream towards the Mouth into Port Phillip Bay. As measured by the ONPG test, if the distance from the sewage plant of where the sample was taken increases, then these samples will exhibit an increase in their absorbance values due to the greater amount of β-galactosidase present and therefore concentration of faecal coliforms. Similarly, in terms of the MPN test, the further away from the treatment plant, the greater the number of pink colonies formed and therefore the concentration of gram-negative lactose fermenting bacteria.

what is an alternative method to MPN method for determining faecal coliform concentration in water samples using a reference

what is the effect of false-positives and false-negative results in the Colilert Method (ONPG test) and how do these affect the concentration of faecal coliforms in water samples?

An environmental scientist collects water samples from streams and rivers near largeindustrial plants and saves exactly 1 liter of water from each sample. Then, back at the lab,the researcher determines the amounts of certain health-jeopardizing bacteria in eachsample. What measurement scale does the measurement of bacteria content reflect?

Context: find a scientific journal (reference date needs to be after 1999) that proves that the Membrane filtration method is better than the MPN method for determining the concentration of faecal coliforms in water samples