\begin{Schunk}
\begin{Sinput}
 m1 = 10
 sd1 = 20
 x <- seq(m1 - 3 * sd1, m1 + 3 * sd1, length = 200)
 prob1 <- dnorm(x, m = m1, sd = sd1)
 plot(x, prob1, ylab = "Probability Density", main = "", 
        type = "l", ylim = c(0, max(prob1) * 1.3))
 m2 = -4
 sd2 = 15
 prob2 <- dnorm(x, m = m2, sd = sd2)
 lines(x, prob2, lty = 2)
 legend("topright", legend = c(paste("mu=", m1, 
        "sigma=", sd1), paste("mu=", m2, "sigma=", 
        sd2)), lty = 1:2)
 abline(h = seq(0, max(prob1), length.out = 5), 
        lty = 5, lwd = 0.3, col = "gray70")
 abline(v = c(m1, m2), lty = 5, lwd = 0.3, col = "gray70")
\end{Sinput}
\end{Schunk}
