Error in course created by xoviat

Community-Created Courses Spanish (Latin-American/Mexican)
1

The word “periodo” does not have an accent. Please fix it in your course. The pronunciation is correct; the accent is wrong.

2

It seems that both forms are accepted: http://dle.rae.es/?id=SdfO44A

3

is it this course?

ps! I also have read and heard that both can be correct depending on location