讀取檔案
dta <- read.table("C:/Users/X510/Desktop/2020-04-13-In-class exercises-2/cigarettes.txt", header = T)
head(dta)## Country consumption death
## 1 Australia 480 180
## 2 Canada 500 150
## 3 Denmark 380 170
## 4 Finland 1100 350
## 5 UK 1100 460
## 6 Iceland 230 60