power point

How many slides do you guys think a power point is to get a good grade? I was wondering because i decided to do that for my extra credit work. Right now i have eight slides along with a video for a visual. i seriously need that extra credit like i don't even want to miss just a point. I wish i had more time to do something like a poster or something cool you know? anyway though i think your just suppose to cover the who what when where and why's and i think i at least did that. well wish me luck lets hope for the best.