Lama atem mochrim et mis'adoteichem
Does the answer have to use the plural 'you' form? My answer with אתה instead of אתם (and appropriate verb and other endings) was marked wrong.
So "for what" can't be used synonymously with "why"? As in: What are you selling your restaurants for. Or is it just that it doesn't sound natural?
בשביל מה אתן מוכרות את המסעדות שלכן?
your sentence is fine. It sounds natural in Hebrew.
Why is it necessary to us את before מסעדותכם in this sentence.
Because you still have an action being committed toward the restaurant. The restaurant is still a direct object, even when conjugated this way, so you must put את directly in front of it.
But why is there no "ה" added to the front of מסעדותיך?
When a noun has a suffix, it is definite by default, so you don't need to add ה to make it definite.
Umm without duolingo Plus this section would be absolutely unquestionably impossible to navigate... and i still dont know how I'm going to get thru this part
כם /כן should be "your"