What is the difference between b and br tag​

Hi plz 11 ! when planning a table, what step comes first: "define the column headers" or "calculate the number of columns/rows"? a. calculate the number of columns/rows b. define the column headers

Donnie does not have powerpoint. which method would be best for elana to save and share her presentation as is? a pdf a doc an rtf a ppt

What is the primary difference between the header section of a document and the body? a. the body is displayed on the webpage and the header is not. b. the header is displayed on the webpage and the body is not. c. the tag for the body is self-closing, but the tags for the headers must be closed. d. the tag for the header is self closing, but the tag for the body must be closed.