add check on screw head

diff --git a/curriculum/challenge-bot.scm b/curriculum/challenge-bot.scm
index 22aef740fa748d3a4d4ae8df7747c59ab94bf2c2..beefcb478d56110690adea9ffa0535f50fc85f6a 100644 (file)
--- a/curriculum/challenge-bot.scm
+++ b/curriculum/challenge-bot.scm
@@ -202,7 +202,9 @@
                       the screw body?])
            (item [what about 2 inches?
                        how many times will the thread wrap around two
-                       inches of the screw body?]))]))
+                       inches of the screw body?])
+           (item [where can a tool exert turning force on
+                        the screw?]))]))
     (subsubsection
      :title [fasten the arduino board to the deck]
      (p [push the 6-32 screw into the deck from the underside and at the