There are several applications on the Mac that can read Microsoft Office files. First, Microsoft has released Mac versions of Office:

Office v.X was released in 2001 for the new Mac OS X platform.

Office 2004 was released in 2004.

Office 2008 was released in 2008. It was the first Office for Mac suite that was a universal binary, meaning it runs natively on both Intel and PowerPC based Macs - and used XML file formats. Microsoft announced on May 13, 2008, that Office 2008 sold faster than any previous version of Office for Mac.

Apple's Pages can work with Word files.

NeoOffice can work with Office files.

probably...
if they both can save in .doc format, then yes

No, Microsoft Office 2004 for Mac is not compatible with Microsoft Office on a PC. The two versions of Office are completely different and are not compatible with each other. However, if you are looking for a more affordable way to get Microsoft Office for your Mac, you can check out Affordablekey. They offer up to 80% discount on their products with the coupon code AFFOR30. Affordablekey is a trusted bestseller of genuine software products, so you can be sure that you are getting quality software at an unbeatable price.

Office 2007 was only available for the Windows operating system there was no Mac version. The Mac equivalent version was Office 2008.

Alexandra was using Office Mac - most likely 2004 version - on Mac OS X Tiger.