The HTTP 415 Unsupported Media Type client error response code indicates that the server refuses to accept the request because the payload format is in an unsupported format. The format problem might be due to the request's indicated Content-Type or Content-Encoding , or as a result of inspecting the data directly. As per RAML input is expected in application/xml.
Hence correct answer is Set a request header with the name Content-Type to a

URI parameter (Path Param) is basically used to identify a specific resource or resources . For eg : the URL to get employee details on the basis of employeeID will be GET /employees/{employeeID} where employees is resource and {employeeID} is URI parameter. Hence option 1is the correct answer