Many Free-Form questions on one Slide

I have a client that wants a calculation table on one slide with several blanks. Thanks to one of the happiness engineers, I have created slides with a few fill-in the blanks using the pick-one buttons on the slide. The problem with this method is that all the answers have to be correct and I would think that filling in that many answers, not knowing which answer is incorrect before getting positive feedback, would be too frustrating. Any ideas?