. <P>
The subscribe_notifier() and unsubscribe_notifier() operations are to subscribe/unsubscribe Stock Broker
clients with the Stock Distributor servers. <P>
The provide_quoter_info() factory operation returns StockQuoter object references that Stock Broker clients can
use to get more information about a particular stock. <P>
The shutdown() operation is a oneway operation which shuts down the object and terminates the application. <P>
The notification_rate attribute stands for the notification frequency th