Yes, not only is it possible, but we strongly recommend it.
With just a single API request you can send up to 200 texts to a classifier or extractor at the same time.
This is the way to get the best performance. Every classification or extraction made (even if they are made in one request) count as a query (eg. a call to a classifier API with 200 texts means 200 classifications = 200 queries). The advantage is that they are made in much less time than if they were made by one call for every text.