Update plan.md

Updated transactions terminology to text records

Author: shshubhe

articles/cognitive-services/language-service/question-answering/concepts/plan.md

@@ -24,7 +24,7 @@ Each [Azure resource](azure-resources.md#resource-purposes) created with questio
 
 ### Resource planning
 
-Question answering throughput is currently capped at 10 transactions per second for both management APIs and prediction APIs. To target 10 transactions per second for your service, we recommend the S1 (one instance) SKU of Azure Cognitive Search.
+Question answering throughput is currently capped at 10 text records per second for both management APIs and prediction APIs. To target 10 text records per second for your service, we recommend the S1 (one instance) SKU of Azure Cognitive Search.
 
 ### Language resource