Question

{x}x is a letter in the word HIPPOPOTAMUS, LIST THE ELEMENTS OF THE SET IN ROSTER NOTATION

Answer 1

Roster notation is just a list of all of the elements of the set. In this case, all of the letters of the word in question. The only thing you should remember is that sets don't contain repetition, so e.g. O would only appear in the set once even though it appears in the word twice.