The Cloud9 app will have two main features - listing all file names (i.e., object names or keys) as well as their sizes in the bucket, and creating a new file/object with the name/key "index.html" within the bucket. Upon serving, the index.html will display these names and sizes. It will print a message "no object available" if the bucket is empty. It has been taught during the tutorial that while creating an object in a bucket, you need to specify the content of the object. The content of the index.html in this case will include the current object names and their sizes. You will get the names and sizes of the objects by implementing the listing feature. You need to embed this information with HTML code to prepare the content of the index.html. The error.html will be very simple and will display a relevant error message, e.g., page not found. Question: what will be the java & html code?