This W3C-unspecified chart was created with R.

using the following commands

svg("R-car_stopping_distances_1920+null.svg", 8,4,8)
layout(t(1:2))
par(mar=c(5, 4, 1, 2) + 0.1)
cars$speed.kph <- cars$speed*1.609344
cars$dist.m <- cars$dist*0.3048
plot(dist.m ~ speed.kph, data=cars, xlab = "Speed (km/h)", ylab = "Stopping distance (m)", las = 1)
null.model <- lm(dist.m~1, data=cars)  #This creates and stores a model ("lm" means "Linear Model").
abline(null.model, col="red")     #"abline" is a simple function that plots a straight line
segments(cars$speed.kph, fitted.values(null.model), cars$speed.kph, 
fitted.values(null.model)+residuals(null.model), col="lightblue")

par(mar=c(5, 5, 1, 1) + 0.1)
plot(residuals(null.model), type="h", ylim=c(-25,25), bty="n",
 xaxt="n", las=2, xlab=NA, ylab="residual stopping distance (m)", col="lightblue")
grid(NA, NULL)
abline(h=0)
points(residuals(null.model))
dev.off()

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