Crossword puzzle clue "answers for short"

How many letters are in the longest answers in this puzzle - or how many of these answers there are

Letter appearing only in down answers; its opposite appears only in across answers

Big letters, for short (and what your answers must be written in to understand the theme)

Short answers?

Newsstand buy, for short—one begins each of the four longest puzzle answers (and also ends the last one)

State short forms strung together in 12 long answers in this puzzle

Answers an invite, for short

Answers, for short