A developer at a company recently created a serverless application to process and show data...

A developer at a company recently created a serverless application to process and show data from business reports. The application's user interface (UI) allows users to select and start processing the files. The Ul displays a message when the result is available to view. The application uses AWS Step Functions with AWS Lambda functions to process the files. The developer used Amazon API Gateway and Lambda functions to create an API to support the UI.

The company's Ul team reports that the request to process a file is often returning timeout errors because of the see or complexity of the files. The Ul team wants the API to provide an immediate response so that the Ul can deploy a message while the files are being processed. The backend process that is invoked by the API needs to send an email message when the report processing is complete.

What should the developer do to configure the API to meet these requirements?