exem_1

data(iris)

library(dplyr)

## 
## Attaching package: 'dplyr'

## The following objects are masked from 'package:stats':
## 
##     filter, lag

## The following objects are masked from 'package:base':
## 
##     intersect, setdiff, setequal, union

result <- iris %>%
  group_by(Species) %>%
  summarise(
    min_sepal_width = min(Sepal.Width),
    max_sepal_width = max(Sepal.Width),
    sd_sepal_width  = sd(Sepal.Width)
  )

print(result)

## # A tibble: 3 × 4
##   Species    min_sepal_width max_sepal_width sd_sepal_width
##   <fct>                <dbl>           <dbl>          <dbl>
## 1 setosa                 2.3             4.4          0.379
## 2 versicolor             2               3.4          0.314
## 3 virginica              2.2             3.8          0.322

library(ggplot2)

ggplot(iris, aes(x = Species, y = Sepal.Length)) +
  geom_boxplot() +
  labs(
    title = "Boxplot Sepal.Length theo Species",
    x = "Species",
    y = "Sepal.Length"
  )