As with many other words ending in -et/-a, the two are simply different versions of the same word. -et words is a major feature of Moderate Bokmål, and -a ones of Radical Bokmål (and Nynorsk). When both -et and -a forms are possible, users should be consistent and stick with one of the endings.
The Language Level symbol shows a user's proficiency in the languages they're interested in. Setting your Language Level helps other users provide you with answers that aren't too complex or too simple.
Has difficulty understanding even short answers in this language.
Can ask simple questions and can understand simple answers.
Can ask all types of general questions and can understand longer answers.
Can understand long, complex answers.
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