2] Cleaning Data: To remove a column 'col' in a dataframe 'data' using null, the command is:data$col <- NULLHow to apply hash strings (a series of unreadable text) to replace important data e.g. full names. https://cran.r-project.org/web/packages/openssl/vignettes/crypto_hashing.html3] For Loops: The code I discussedFor (i in commands to be written here in a series of lines}4] Vectorisation: The explanation of apply (and related commands like 'lapply') I used is here https://www.guru99.com/r-apply-sapply-tapply.html