please solve the problem on detailed steps showing how to calculate area under each graph using trapezoid rule

Example #$3$

A parallel arrangement of six sand filters at a water treatment plant operate at a total flow

rate of $52,920\frac{m^3}{?}$ day $(14$ MGD $).$ The HRT in the filter box $($volume above the filters$),$ the

filter media, and the underdrain is $50$ min $.$ Chlorine is added just ahead of these filters to

prevent microbial growth on the media, which would otherwise cause premature clogging

and reduce the time between required backwashing. The municipality is interested in

determining the residence time distribution characteristics of water in the filters because

this information can be used to estimate the disinfection of Giardia cysts occurring as a

result of chlorine dosing. A pulse input $(2\mathrm{.}9kg)$ of a conservative tracer $(NaCl)$ is

introduced. Following the pulse input, the NaCl concentration is measured in the manifold

which collects the combined filtrate from all six filters. The resulting data for tracer

concentration $C_t$ as a function of time are given in the following table.

Characterize the residence time distribution for the filters

Compare the actual residence time to the hydraulic retention time. What is the effective

reactor volume based on the residence time and how does this compare to the reactor

volume based on the hydraulic retention time?

What conclusions can you draw from this comparison?

Plot C curve, E curve, Calculate mean residence

time, variance, skewness of the curve, and F curve