"What did you do on Thursday?"
Translation:Что ты делал в четверг?
Wouldn't Что ты делал в четверг? mean "what were you doing on Thursday?", as in what activities did you do all day (although I concede that you can express this meaning in English with the constructo "what did you do on...?").
I think this should be что ты сделал в четверг? and the answer should be accepted.