ClearAll;Clear[a];Clear[b];Clear[p];Clear[q];
$DefaultFont = {"Times-Roman",10};
Needs["Graphics`Graphics`"];
ff[t_]:= 350(3 - 10 t)(20 t - 1)(7 - 20 t)/9;
f1[t_]:= (192500 t)/9;
f2[t_]:= -(980000 t^2)/9;
f3[t_]:= (1400000 t^3)/9;
f[t_]:= -2450/3 + f1[t] + f2[t] + f3[t];

plot11 = Plot[f1[t],{t,1/20,7/20},AxesLabel->{"t","y"},
	PlotLabel -> "y = g(t)",
	Ticks->{Join[{{0.15,0.15},{0.25,0.25}},
	Table[{0.025i," "},{i,14}]],Table[{2000i,2000i},{i,0,3}]},
	PlotRange->{{0,7/20},Automatic}];
vert11 = Graphics[{Dashing[{0.01,0.01}],Line[{{0.3,0},{0.3,f1[0.3]}}]}];
plottl = Show[plot11,vert11];

plot21 = Plot[f2[t],{t,1/20,7/20},AxesLabel->{"t","y"},
	PlotLabel -> "y = h(t)",
	Ticks->{Join[{{0.15,0.15},{0.25,0.25}},
	Table[{0.025i," "},{i,14}]],Table[{-4000i,-4000i},{i,0,3}]},
	PlotRange->{{0,7/20},Automatic}];
vert21 = Graphics[{Dashing[{0.01,0.01}],Line[{{0.3,0},{0.3,f2[0.3]}}]}];
plotml = Show[plot21,vert21];

plot31 = Plot[f1[t]+f2[t],{t,1/20,7/20},AxesLabel->{"t","y"},
	PlotLabel -> "y = s(t) = g(t) + h(t)",
	Ticks->{Join[{{0.15,0.15},{0.25,0.25}},
	Table[{0.025i," "},{i,14}]],Join[{{1000,1000}},Table[{-2000i,-2000i},{i,0,3}]]},
	PlotRange->{{0,7/20},Automatic}];
vert31 = Graphics[{Dashing[{0.01,0.01}],Line[{{0.3,0},{0.3,f1[0.3] + f2[0.3]}}]}];
plotbl = Show[plot31,vert31];

	
plot12 = Plot[f3[t],{t,1/20,7/20},AxesLabel->{"t","y"},
	PlotLabel -> "y = w(t)",
	Ticks->{Join[{{0.1,0.1},{0.25,0.25}},
	Table[{0.025i," "},{i,14}]],Table[{2000i,2000i},{i,0,3}]},
	PlotRange->{{0,7/20},Automatic}];
vert12 = Graphics[{Dashing[{0.01,0.01}],Line[{{0.225,0},{0.225,f3[0.225]}}]}];
plottr = Show[plot12,vert12];
	
plot22 = Plot[f1[t]+f2[t]+f3[t],{t,1/20,7/20},AxesLabel->{"t","y"},
	PlotLabel -> "y = s(t) + w(t)",
	Ticks->{Join[{{0.1,0.1},{0.25,0.25}},
	Table[{0.025i," "},{i,14}]],Table[{100i,100i},{i,8,12}]},
	PlotRange->{{0,7/20},Automatic}];
vert22 = Graphics[{Dashing[{0.01,0.01}],Line[{{0.225,800},{0.225,f1[0.225] + f2[0.225] + f3[0.225]}}]}];
plotmr = Show[plot22,vert22];
	
plot32 = Plot[f[t],{t,1/20,7/20},AxesLabel->{"t","y"},
	PlotLabel -> "y = s(t) + w(t) - 2450/3",
	Ticks->{Join[{{0.1,0.1},{0.25,0.25}},
	Table[{0.025i," "},{i,14}]],Automatic},
	PlotRange->{{0,7/20},Automatic}];
vert32 = Graphics[{Dashing[{0.01,0.01}],Line[{{0.225,0},{0.225,f[0.225]}}]}];
plotbr = Show[plot32,vert32];
	
Show[GraphicsArray[{{plottl,plottr},
	{plotml,plotmr},{plotbl,plotbr}}],
	PlotLabel->"Figure 2.4"]