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Exact Numbers Obtained when you count objects 2 soccer balls 1 watch 4 pizzas Obtained from a defined conversion factors 1 foot = 12 inches 1 meters = 100 cm Not obtained with measuring tools Do not limit the # of sig figs in the answer. Learning Check A. Exact numbers are 1. measured values 2. count values 3. defined conversion factors B. Measured numbers are obtained by (from) 1. using a measuring tool 2. counting 3. defined conversion factors Learning Check Classify each of the following as an exact (1) or a measured (2) number. A.___Gold melts at 1064°C 2 B.___1 1 yard = 3 feet C.___A red blood cell with diameter 6 x 10-4 cm 2 D.___There were 6 hats on the shelf 1 E.___A can of soda contains 355 mL of soda 2