ask about drill bit

diff --git a/guide/challenge-bot-questions.org b/guide/challenge-bot-questions.org
index c7ce82a53f270f888dc71d6079dcd663d2b333ef..ab338e64e58c15588036f400530a856add8d66e3 100644 (file)
--- a/guide/challenge-bot-questions.org
+++ b/guide/challenge-bot-questions.org
@@ -12,3 +12,6 @@
        bolt used to hold the arduino?
     3. why did we drill through the arduino, rather than marking holes
        and using the drill to make holes where the marks were?
+    4. how does the drill hold onto the drill bit?
+    5. what would happen if the drill bit teeth were not flat on the
+       drill bit?