from the table in mac Berthouex and Brown $(2013$ where the parameters for calculating acute and hardness can be found, the parameters for chromium lll f the acute and chronic toxicity criteria are given as: ma$=0\mathrm{.}8190,$ bA$=3\mathrm{.}7256$ and CFcmc$=0\mathrm{.}316,$ Mc$=0\mathrm{.}8190,$ bc$=0\mathrm{.}6848$ and CFccc$=0\mathrm{.}860.$ if the water hardness is $188\mathrm{.}3$mg$/$lCaC$03,$ what is the acute toxicity criterion?