Big data analytics with R exercise questions, need RMD file that will run on my mac and pdf file of the output

1. What does it mean to “calculate a statistic of interest for each level of a factor”?
2. What does the read.table.ffdf() function do to enable R to work with large data sets? Describe the resulting data structure
3. Compare read.table() with read.table.ffdf() in terms of speed, size of output, usage of ram
4. Errata:
   1. • be sure to set your temp dir inside your working director and identify it for R with the options() function.
      • if your R can’t find any functions that end in .ffdf, prepend those functions with ff::: like so ff:::dimnames.ffdf()
5. Calculate the mean departure delay for each city of origin.

Files to work on this and code are found here: https://github.com/PacktPublishing/Big-Data-Analyt…

Select the airline_id CSV and flights_sep_oct15.zip, I cannot just copy-paste the code as given in the text since it will show 100% copied. Work your magic and answer the 5 questions above. Thank you!