answer: b. 300
in the graph, the interval is increasing by 100. therefore, is x=12, y=660
in the chart, the interval for y is increasing by 30. therefore, if x=12, y=360
(work below)
x| 8, 9, 10, 11, 12
y| 240, 270, 300, 330, 360
you subtract 660-360. the answer is 300.