--- a/handouts/ho01.tex	Fri Sep 16 11:07:02 2016 +0100
+++ b/handouts/ho01.tex	Wed Sep 28 06:57:31 2016 +0100
@@ -108,7 +108,7 @@
 
 The questions is whether the Chip-and-PIN system used with
 modern credit cards is more secure than the older method of
-signing receipts at the till. On first glance the answer seems
+signing receipts at the till? On first glance the answer seems
 obvious: Chip-and-PIN must be more secure and indeed improved
 security was the central plank in the ``marketing speak'' of
 the banks behind Chip-and-PIN. The earlier system was based on