plot(dat[, 1], dat[, 2], col = "blue", pch = 18, xlim = c(min(dat), max(dat)), ylim = c(min(dat), max(dat)))
points(dat[, 1], dat[, 3], col = "red", pch = 15)
points(dat[, 1], dat[, 4], col = "green", pch = 17)
points(dat[, 1], dat[, 5], col = "orange", pch = 4)