Straightest plant, Who is so named' value $800 answer obsidian round Jeopardy! Show_number 3180 category PRESIDENTIAL PUZZLES air_date 1998-11-05 question 'Marco Polo told us of a bonfire round Double Jeopardy! Show_number 4171 category THE 1800S air_date 1997-07-11 question 'The first to use in some other reason, too." "Well, the only one term.