> png("monopolioa.png")
> plot.new()
> par(bty="l")
> par(mfrow=c(2,1))
>  par(mar=c(5.1,4.1,0.1,2.1))
>  par(oma=c(0,0,4,0))
> x=c(0)
> y=c(0)
> plot(x,y,pch='.',lwd=0,col="black",xlab="",
ylab="Prezioa - Sarrera marjinala",cex.lab=0.7,xaxs="i",yaxs="i",
xaxt="n",yaxt="n",xlim=c(0,11),ylim=c(-8,22))
>axis(1,at=seq(0,10,by=1),
labels=c("0","1","2","3","4","5","6","7","8","9","10"),
tck=-0.05,cex.axis=0.7)
> axis(2,at=seq(-8,20,by=4),
labels=c("-8","-4","0","4","8","12","16","16"),
tck=-0.05,cex.axis=0.7,las=1)
> abline(h=0,lty=3)
>  a=c(0,10)
>  b=c(20,0)
>  lines(a,b,lwd=4,col="red")
>  c=c(0,6)
>  d=c(20,-4)
>  lines(c,d,lwd=4,col="green")
>  text(7,16,"Eskaria: q=10-p/2",cex=0.7,font=2)
> text(2,4,"Sarrera marjinala: 20-4q",cex=0.7,font=2)
>  e=c(5,5)
>  f=c(-8,0)
>  lines(e,f,lty=3)
>  x=c(0)
>  y=c(0)
>plot(x,y,pch='.',lwd=0,col="black",xlab="Kopurua",
ylab="Sarrera totala",cex.lab=0.7,
xaxs="i",yaxs="i",xaxt="n",yaxt="n",xlim=c(0,11),ylim=c(0,70))
>axis(1,at=seq(0,10,by=1),
labels=c("0","1","2","3","4","5","6","7","8","9","10"),
cex.axis=0.7,tck=-0.05)
>axis(2,at=seq(0,60,by=10),
labels=c("0","10","20","30","40","50","60"),
cex.axis=0.7,las=1,tck=-0.05)
>  x=seq(0,10,length=101)
>  y=20*x-2*x^2
> lines(x,y,lwd=4,col="blue",type="l")
>  text(7,55,"Sarrera totala: qp=20q-2q^2",cex=0.7,font=2)
> a=c(5,5)
>  b=c(0,50)
> lines(a,b,lty=3)
>  c=c(0,5)
>  d=c(50,50)
> lines(c,d,lty=3)
> dev.off()