# 1 d

tires = 4;

w=7500 ; every=500;
d.w = 10; n.trials = w/d.w; lambda = 1/5000; p = lambda*d.w ;

par(yaxt = "n")

plot(c(0,7500), c(0.5,tires+0.5), "s",col = "white",
    xlab="Km",
    ylab="TireLocation", frame.plot=T )

for (tire in 1: tires) abline(h= tire,   col ="lightgray")
for (km in seq(every,w,every) ) abline(v= km,   col ="lightgray")

 for (k in seq(d.w,w,d.w) ) { 
 for (tire in 1: tires) {   
    if (runif(1) < p) { points(k,tire+0.05,cex=2,col="red") }
    else points(k,tire,cex=0.5)
    }
}