Interaction makes video game the most successful entertainment ever. Of course video game is a kind of arts. Different from other art forms, we can see wisdom of not only the developers but also the players.
Honestly, math section of this 1869 test is still kind of joke for Chinese high school students. Getting full mark is easy for those well educated middle school students, say, up to about 30 percent won't be a overstated figure.
Annotation benefits mostly when you view the document again, which means your browser needs to reserve the file for some time like a month or longer, this does not sound like everyone will do.