A developer wants to programmatically inject Contacts into a journey via REST API. What is the recommended route using POST data extension fields and values?

Customer data has been imported into a staging data extension and needs to be normalized before adding into the master data extension. A text field named 'birthday' contains date values in various formats. Some of the values are valid dates, but some are not.
Which SQL keywords and functions could be used to write the query'' Choose 2 answers

A developer wants to include a comment within an AMPscript code block for the benefit of other developers who will be reviewing the code.
Which syntax should the developer use?

A developer receives Error Code 5 when performing a SOAP API call. The error states: "Cannot Perform 'Post' on objects of type 'SentEvent'".
What could be the issue?

New subscribers at Northern Trail Outfitters (NTO) are added to a data extension. NTO would like to send these subscribers a welcome series with Journey Builder.
What would allow the data extension to be selected for journey entry'