The graphs show the percentage of high school seniors who used alcohol or marijuana during...

The graphs show the percentage of high school seniors who used alcohol or marijuana during the 30 days prior to being surveyed for the University of Michigan’s Monitoring the Future study.

The data can be described by the following mathematical models:

Use this information to solve Exercise.

a. Use the appropriate line graph to determine the percentage of seniors who used alcohol in 2000.

b. Use the appropriate formula to determine the percentage of seniors who used alcohol in 2000. Does the formula underestimate or overestimate the actual percentage displayed by the graph? By how much?

c. Use the appropriate line graph to estimate the percentage of seniors who used marijuana in 2000.

d. Use the appropriate formula to determine the percentage of seniors who used marijuana in 2000. How does this compare with your estimate in part (c)?

e. For the period from 1980 through 2009, in which year was alcohol use by seniors at a maximum? Estimate the percentage of seniors who used alcohol in that year.