Partitioning - 10g R2

Hello everyone

We have inherited a system where on one of the table, multiple type of partitioning has been used
Being new to partitioning, we would appreciate any help we can get to understand how the partitioning
would chunk out the data in the table

Here is the DDL of the table

  CREATE TABLE INVOICE_DATES                                                                               
   ( FILE_NO NUMBER(10,0),                                                                                           
 TRC_DT_NO NUMBER(5,0),                                                                                        
 DT_TRC_SHIP NUMBER(8,0) NOT NULL ENABLE,                                                                  
 TM_TRC_SHIP NUMBER(4,0) NOT NULL ENABLE,                                                                  
 MODIFIED_BY CHAR(12) NOT NULL ENABLE,                                                                               
 DATE_UPDATED NUMBER(8,0) NOT NULL ENABLE,                                                                           
 TIME_UPDATED NUMBER(4,0) NOT NULL ENABLE,                                                                           
 CUST_NO CHAR(10) NOT NULL ENABLE,