Missing Solution in Chapter 02

[marcfargas]

Hi. Just found the book and taking a quick look. Looks funny! Noticed that:

Chapter 02 has three exercises:

joyofelixir/_includes/ch/2.html

Lines 121 to 131 in dd49c1f

	<section>
	<h3>Exercises</h3>
	<ul>
	<li>If we store the number of seconds in a day using this code: <code>seconds = 86400</code>, calculate using that
	variable how many hours there are in 30 days.</li>
	<li>Create a variable called <code>name</code>, store a string in it and place the value of that variable in another
	string.</li>
	<li>The line <code>5 / "four"</code> shows an error. Think about why this error might happen.</li>
	</ul>
	</section>

But the solutions have only two. The second exercise is missing.

Maybe:

name = "Snoopy"
greeting = "Hello, #{name}"