4  Exercises (Chapter 4)

1. Restyle the following pipelines following the guidelines above.

   flights|>filter(dest=="IAH")|>group_by(year,month,day)|>summarize(n=n(),
   delay=mean(arr_delay,na.rm=TRUE))|>filter(n>10)
   
   flights|>filter(carrier=="UA",dest%in%c("IAH","HOU"),sched_dep_time>
   0900,sched_arr_time<2000)|>group_by(flight)|>summarize(delay=mean(
   arr_delay,na.rm=TRUE),cancelled=sum(is.na(arr_delay)),n=n())|>filter(n>10)

   Answer

   # Your R code here

   Provide an easy way to restyle the code.