Adam went into Watson's to make a purchase. He asked about pricing. "One will cost you $2 , eight will $2 cost , seventeen will cost $4 , and six thousand will cost $8." "All right, I’d like thirty-five," said Adam. What was he buying, and what did he pay?

Which sum or difference identity would you use to verify that cos (180° - q) = -cos q? a.) sin (a -b) = sin a cos b – cos a sin b b.) cos (a -b) = cos a cos b – sin a sin b c.) cos (a -b) = cos a cosb + sin a sin b d.) sin (a + b) = sin a cos b + cos a sin b