time<-c(66,37,18,31,85,63,73,83,65,80) df<-length(time)-1 s.sq<-var(time) u.chi<-qchisq(0.005, df=df, lower.tail=F) u.chi l.chi<-qchisq(0.995, df=df, lower.tail=F) l.chi LCL<-(df*s.sq/u.chi) UCL<-(df*s.sq/l.chi) LCL;UCL