I WILL GIVE DISLIKES $!!!$ IF ANYTHING WRONG HAPPENS IN MY QUESTION, BETTER SKIP IT$!!!$ "Suppose v is a vector whose elements are number $($of type double$).$

Using the list of basic functions VB$13$ from the lecture notes, fill in each blank with a function name so that the completed R code below results in TRUE when executed successfully.

length$($v$)*?($v$)==?($v$)"$