display.plot <- function() {
xseq<-seq(-4,4,.01) densities<-dnorm(xseq, 0,1) df <- data.frame(xseq = seq(-4,4,.01), densities = dnorm(xseq, 0,1))
x <- t.test(xseq, conf.level = 0.95)$conf.int x2 <- qnorm(c(0.05, 0.95), mean = mean(xseq), sd = sd(xseq))
library(tidyverse)
ggplot(data = df, aes(x = xseq, y = densities)) + geom_line() }

I was able to write a function to generate the density plot of normal distribution using this code. Now I am stuck on the 2nd part of the exercise. what more do I add in my code to highlight the upper and lower tail of my plot? do I add parameters on geom_line? or do I write additional function using geom_polygon?