# R-program for Supplementary Exercises 7.58 and 7.59 of IPS7e

lessons <- read.csv("r:/Chapter 7/ex07_058.csv")

# 7.58
stem(lessons$change)
summary(lessons$change)
t.test(lessons$change, conf.level=0.95)

# 7.59
t.test(lessons$change, alternative="greater", mu=0)