tmpar <- par(mar=c(3.1,2.1,.5,.5),mfrow=c(1,2))

attach(bactroom)
interaction.plot(temp,bact,bill,type="b",yaxt="n",xlab="",ylab="")
mtext("(a) temp",1,2)
mtext("mean of bill",2,1)
#tmp <- c(39,40,41)
detach()
attach(oocyte)
interaction.plot(h89,fors,asper,type="b",yaxt="n",xlab="",ylab="")
mtext("(b) h89",1,2)
mtext("mean of arcsin percent",2,1)
#tmp <- c(20,60,100)
detach()

par(tmpar)