I cussed at my dad. What do I say to him now?

In all seriousness, he was being VERY disrespectful in a childish way as an adult & also a father no less! Had it been one of my children, I would have been far more respectful & even asked if I could be of any help. My Daughter is going to college for teaching, I've also gone to college for an engineering degree, so KNOW how important it is to be prepared for your subjects in order to do your best. I help her EVERY DAY with her homework & am proud she's on the honor roll! I feel HE should take his words he said to you regarding "respect" & LEARN the true meaning of them as they go BOTH ways, he sure is NO exception. To be honest I can't blame you for your feelings as to the way he mistreated you. This IS one hard decision to make as I feel YOU were in the rite! However, since it was your father who you are "suppose to show respect to/for", I guess the best thing would be to say you were under a LOT of pressure knowing this was a very important final you were studying for & that's all you had on your mind at that time. Due to this fact was the reason I got upset because I was trying to study for this important test & was unable to concentrate properly with the radio playing so loudly. Thus the reason for me loosing my temper. In a way you're explaining the reason for the "blow up", but in a way you're not apologizing to him for his lack of respect to you. This is the way I would handle it as I truly don't feel you do owe him an apology, but at least you're not "brushing it under the rug" so to speak, you're acknowledging the incident & I feel in this case is all that's necessary. The best to you, I trust you did well on your test.*