> x <- rnorm(100)
> summary(x)
   Min. 1st Qu.  Median    Mean 3rd Qu.    Max.
-2.3730 -0.7349  0.1644  0.1224  0.8297  3.0990
> y <- rnorm(1000)
> plot(y, pch = 19, xlab = "", ylab = "", main = "random numbers",
+     col = "blue")

test4-003.jpg