1. This task continues the work begun in Task 1. In your first table, what restrictions need to be put on the various attributes of the data objects? Formulate at least two such constraints as validators. You might want to consult the documentation at http://guides.rubyonrails.org/active_record_validations.html to see what types of validations are available.

2. Make sure the automatically generated tests still succeed. If necessary, modify the (automatically generated) fixtures and test routines to take into account the constraints you put in place in part 1.

3. Formulate one test that checks whether validation works as intended.

4. Prepare a short (less than one page) report on the progress on your app and hand it up in class next Wednesday.