Oracle Database Discussions

I am a novice in Oracle Technology. My problem is as follows:

I have Oracle Database 10gR2 software installed on a Windows server 2003 (with Service Pack 2) machine in the local network. The Oracle instance name is 'T27'. The 'T27' instance is reading a database. This instance and database has been created by a person previous to me.

My requirement is to have another instance by the name, say 'T28', and this new 'T28' instance is to read another new database (different from the existing one) that I will be creating.

Specifically:

[1] How do I create an Instance with the Oracle Database 10gR2 server software?
[2] How do I create a separate database with the Oracle Database 10gR2 server software?
[3] How do I make this newly created Instance read the newly created database?

Additionally I have a '.dmp' file available with me. This was the backup copy of a database take by the person before me.

[4] How do I create a new database from the '.dmp' file?


// Please note that there already exist an instance and a database in the current installation.
// I want to add an instance as well as a new database.
// The database is to be created from the .dmp file.