All others are names for level-based measure but Sales is a base measure.

A: OBIEE Federated Repository
Instead of moving data in to a single database, OBIEE - BI Administration can access multiple databases and create a single federated repository.OBIEE BI Answer uses this federated repository and build the ad-hoc reports and dashboards.
D: Repository Metadata Consists of 3 Layers
* The Physical Layer (Schema)
* The Business Model and Mapping Layer
* The Presentation Layer
Note:

Explanation
When you need to model many-to-many relationships between dimension tables and fact tables, you can create a bridge table that resides between the fact and the dimension tables. A bridge table stores multiple records corresponding to that dimension. In the Administration Tool, General tab in the Logical Table dialog box contains a check box that you can select to specify that a table is a bridge table.
A bridge table allows you to resolve many-to-many data relationships.
Reference; OBI Server Administration Server Guide, Version 10.1, Identifying Bridge Tables

Explanation
Priority group
You can set priority group numbers to determine which logical table source should be used for queries for which there is more than one logical table source that can satisfy the requested set of columns.
For example, you might have user queries that can be fulfilled by both a data warehouse and an OLTP source.
Often, access to an operational system is "expensive," while access to a data warehouse is "cheap." In this situation, you can assign a higher priority to the data warehouse to ensure that all queries are fulfilled by the data warehouse if possible.
Note that the priority group of a given logical table source does not always ensure that a particular query will be fulfilled by that source.
Priority Group Designation
0 the highest-priority source (the default)
1 a lowest-priority source

Dimensional Modeling - Slowly Changing Dimensions
* Type 1 - Overwrite Original Value
A change does not require tracking
* Type 2 - Add a new record
With Type II SCD, a new version of the dimension record (row) is created, and the existing version is marked as history.
Each row does not correspond to a different instance of an entity but a different "state", a "snapshot" of the instance at a point in time.
Note: Tracking changes in dimension is referred in datawarehousing as slowly changing dimensions.
In the source system a lot of changes are daily made :
new customers are added,
addresses are modified,
new regional hierarchies are implemented,
or simply the product descriptions and packaging change.
These sorts of changes need to be reflected in the dimension tables and in several cases, the history of the changes also needs to be tracked.
By remembering history, we are then able to look at historical data and compare it to their current situation.