Yes, it most certainly should have a question mark but we are not able to make any changes to the original sentences. We are working on a new tree in which we will correct these errors...and include much richer material.
Thanks for the notification.
Since you are working on a new tree to include much richer material, I do hope you take into account my comments on teaching us practical sentences that deal with real-world situations in which the sentences you teach us will be useful. If you study up on the difference between teaching grammar and teaching situational conversation, you will see that the emphasis now is in teaching language competencies having to do with situations. You can read up on this if you study the Common European Framework of Reference for Languages https://en.wikipedia.org/wiki/Common_European_Framework_of_Reference_for_Languages