update exercise answer

Author: shrimadhav u k

Slide/exercise.html

@@ -51,10 +51,17 @@ <h2><font color="yellow">Exercise</font></h2>
 				<section>
 					<pre><code data-trim contenteditable>
 #!/bin/bash
-echo "Sleeping for $1 minutes"
-sleep $(expr $1 \* 60)
-echo -e "\a" # Alarm
-echo "Time up"
+
+# This script asks the user for a time, waits the specified amount
+# of time, and shows an alert dialog.
+
+TIME=$(zenity --entry --title="Timer" --text="Enter a duration for the timer.\n\n Use 5s for 5 seconds, 10m for 10 minutes, or 2h for 2 hours.")
+
+sleep ${TIME}
+
+cvlc --play-and-exit Beep-sound.ogg # Alarm
+
+zenity --info --title="Timer Complete" --text="The timer is over."
 					</code></pre>
 				</section>