In order to share an XML file among different systems and programs, this XML file need to checked well, what are the two things to be done?

Question

/////////////////////////////////employees.xml////////////////////////////////////////////
<?xml version="1.0" encoding="UTF-8"?>
<employees>
<employee>
<first_name>Linda </first_name>
<middle_name>P.</middle_name>
<last_name>Jone</last_name>
<home_phone>386-333-2321</home_phone>
</employee>
<employee>
<first_name>Tom </first_name>
<last_name>Smith</last_name>
</employee>
<employee>
<first_name>Hilda </first_name>
<last_name>Parham</last_name>
<home_phone>386-455-5675</home_phone>
</employee>
</employees>