# set sample size and number of samples
set.seed(1)
n <- 2
reps <- 10000

# perform random sampling
samples <- replicate(reps, rnorm(n,2.5,1.118)) # 2 x 10000 sample matrix

# compute sample means
sample_mean <- rep(NA, reps)

for (i in 1:reps) {
  sample_mean[i] <- mean(samples[,i])
}

# check that 'sample_mean' is a vector
is.vector(sample_mean) 

(mean(sample_mean))
(var(sample_mean))
(sd(sample_mean))

hist(sample_mean,  freq=F, col="grey", xlab="", xlim=c(-1, 6), breaks=100)
par(new=T)
plot(density(sample_mean), axes=F, main="", xlim=c(-1, 6), lwd=2, col="blue")