Help me! big troubles with ArcGIS Desktop 10 Free Trial extensions

[GiacomoRossi]

Hello, I am an italian G.I.S. student and I need as soon as possible these extensions for my graduation thesis :
    ArcGIS 3D Analyst
    ArcGIS Geostatistical Analyst
    ArcGIS Network Analyst
    ArcGIS Schematics
    ArcGIS Spatial Analyst
    ArcGIS Tracking Analyst
    ArcGIS Data Interoperability
    ArcGIS Publisher
    ArcScan for ArcGIS
    Maplex for ArcGIS
In this webpage http://www.esri.com/software/arcgis/arcgis-for-desktop/free-trial.html is written that in the ArcGIS Desktop 10 free trial version these extensions are included, but after installing the software, when I open ArcMap, I can't use any of these extensions (I specified during the authorization that I want in the evalution extensions all of these...). I need overall IDW and spatial analyst tools for my job. What should I do? I conctacted an italian esri employee and he told me that probably I have to use an ArcInfo license to use these tools. If it was like these, it is not true what is written here http://www.esri.com/software/arcgis/arcgis-for-desktop/free-trial.html
So can you help me, please?

[EricKrause]

Did you enable the extensions?

To do this, open ArcMap, and open the "Customize" pulldown menu, and choose "Extensions."  Check the box next to each extension that you want to enable.

If that isn't the problem, please contact customer support.

[GiacomoRossi]

Hi! thank you very much, you solved my problem, I didn't know I could enable the extensions in this way :)! But I think it should be written in the installation explanation, shouldn't it?
By the way, I don't have the customer support number, or I don't manage to find it my pc. How can I concact it, if it is necessary?

[EricKrause]

https://service.esri.com/index.cfm?fa=homepage.feedback.customer_serviceform

If you ever need to contact customer support, that page has the info.