How does a historian draw conclusions from a chart?

a. by noting the perspective of the chart’s author
b. by identifying the relationships between bits of data
c. by locating cause and effect through sequencing
d. by observing how the information in the chart has changed since it’s creation

it think it might be b but i’m not sure

Dominic and stacy each have a stamp collection. dominic has six fewer stamps than three times the number of stamps stacy has. dominic and stacy decide to give all of their stamps to their younger sister, mary. if stacy had s stamps, which expression represents the number of stamps that mary received? a. (3s − 18)(3s − 6) b. 2s − 18 c. 4s − 6 d. 4s − 18