Linear Fit Models for data which is not quite linear

This is problem 1 from HW of Section 3.4.  We are going to: 
(a) plot the data,
(b) check to see if it is linear in appearance, 
(c) compute the line of best fit for the data, and 
(d) plot both the data and the line of best fit together.

This notebook can be used  to assist with many of the problems from Section 3.4.

ArrestData = {{0,5.85},{1,5.54},{2,4.72},{3,4.70}};

ListPlot[ {ArrestData}, PlotMarkers->{"X"}, PlotStyle->{Black}, PlotLegends->{"Arrest Data"}, PlotLabel->"Federal Meth arrests, in thousands"]

DPlot =ListPlot[ {ArrestData}, PlotMarkers->{"X"}, PlotStyle->{Black}, PlotLegends->{"Arrest Data"}, PlotLabel->"Federal Meth arrests, in thousands",PlotRange->{{-1,5},{0,10}}]

ArrestBestFitLine = LinearModelFit[ArrestData,{1,t},t]

LPlot = Plot[ArrestBestFitLine[t],{t,0,6},PlotStyle->{Blue,Thickness[0.005]},PlotLegends->{"Line of Best Fit"}]

Show[{DPlot, LPlot}, PlotRange->{{-0.5,6},{0.0,10}}, AxesOrigin->{0,0}]

ArrestData

{ArrestBestFitLine[0],ArrestBestFitLine[1],ArrestBestFitLine[2],ArrestBestFitLine[3],ArrestBestFitLine[4]}