A developer wants the ability to roll back to a previous version of an AWS Lambda function in the event of errors caused by a new deployment.
How can the developer achieve this with MINIMAL impact on users?

A company's fleet of Amazon EC2 instances receives data from millions of users through an API. The servers batch the data, add an object for each user, and upload the objects to an S3 bucket to ensure high access rates. The object attributes are Customer ID, Server ID, TS-Server (TimeStamp and Server ID), the size of the object, and a timestamp. A Developer wants to find all the objects for a given user collected during a specified time range.
After creating an S3 object created event, how can the Developer achieve this requirement?

A user has created a mobile application which makes calls to DynamoDB to fetch certain data.
The application is using the DynamoDB SDK and root account access/secret access key to connect to DynamoDB from mobile. Which of the below mentioned statements is true with respect to the best practice for security in this scenario?

A company wants to migrate its web application to AWS and leverage Auto Scaling to handle pear workloads. The Solutions Architect determined that the best metric for an Auto Scaling event is the number of concurrent users.
Based on this information, what should the Developer use to autoscale based on concurrent users?

Which of the following is chosen as the default region when making an API call with an AWS SDK?