一个课程评估网站，操作如下：
- Setup a Cloud9 environment for the course.
- In your Cloud9 terminal, type the following command to clone the repository to your development workspace:
- Then cd rottenpotatoes-rails-intro to change to the app's directory.
- Run the command bundle install --without production to make sure all the gems (libraries) used by the app are in place.
- Run bundle exec rake db:setup to create the initial database.
- Run rails server -p $PORT -b $IP to start the app. Cloud9 will pop up a window showing the URL to visit in your browser to interact with the running app.