font size="4" color="blue">
17
x
x + 17
</font></pre><font color="black">If you type an expression in interactive mode, the interpreter
<b>evaluates</b> it and displays the result:
</font><pre><font size="4" color="blue">
&gt;&gt;&gt; 1 + 1
2
</font></pre><font color="black">But in a script, an expression all by itself doesn't
do anything! This is a common
source of confusion for beginners.<br />
</font><div align="left"><font color="black"><b>Exercise&nbsp;1</b>&nbsp;&nbsp;<em>
Type the following statement