x <- rnorm(1000, mean = 5, sd=5) hist(x)
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qqnorm(x,col="red",pch=19) qqline(x,col="black")
sapply(1:100,function(i)sample(x,10,replace = T)) |> colMeans() |> mean() # 4.99705893538348 sapply(1:100,function(i)sample(x,10,replace = T)) |> colMeans() |> sd() # 1.5179249240205