Need IMMEDIATE help in MatLab...PLEASE

A lake (Figure 1) receives fresh water from a river that continuously flow in and out of the lake. Due to less outdoor activity during Covid-19 pandemic, a pollutant concentration in the lake decreases exponentially over time. The now concentration, Cnew of the pollutant in the lake that changes with a step size of time, ts can be estimated by the following equation: Cnew=Cold+(2et1.5Cold)(ts) where Cold= previous or initial pollutant concentration (tonnes/gallon). Synthesis a MATLAB user-define function to estimate reduction curve of the pollutant concentration over the interval from t=0 to 2 years using a step size of 0.1 year and initial condition of pollutant concentration is 15 tonnes/gallon. Figure 2 shows the expected programming output. pollutant (0,2,0.1,15) After 2 years the pollutant concentration drop to 0.934 tonnes/gallon. fx>> Figure 2: The expected programming output of a MATLAB user-define function. for end fprintf plot grid end