# install.packages("dplyr") once
library(readr); library(dplyr)
sales <- read_csv("sales.csv") |> mutate(amount = qty * rate)
sales |> filter(region == "North") |> arrange(desc(amount)) |> head(5)
sales |> group_by(region) |> summarise(orders = n(), sales = sum(amount)) |> arrange(desc(sales))