Which file extension indicates a text document? .ppt .tst .pdf .txt

Ihave buncha points. does anyone want any?

If your accelerator suddenly gets stuck what should you do

Jason works as an accountant in a department store. he needs to keep a daily record of all the invoices issued by the store. which file naming convention would him the most? a)give the file a unique name b)name the file in yymmdd format c)use descriptive name while naming the files d)use capital letters while naming the file