Figured out that current implementation is false
Added todo/refactoring tasks to interface
Added "isValid" method to abstract
"in between commit"
Moved logic into getPercentageOfAccuracy
Added typcast to (int) to getPercentaceOfAccuracy since we are not interested in after comma numbers
Finished free text answer test
Renamed "SelectedOpportunities" to "EnteredOpportunities"
Removed selectedOpprotunities in tests
Added InvalidArgumentException to addValidOpportunity and addSelectedOpportunity
Added test for new exceptions.