options: Relate the domain of a function to its graph and, where applicable, to the quantitative relationship it describes.  For example, if the function h(n) gives the number of person-hours it takes to assemble n engines in a factory, then the positive integers would be an appropriate domain for the function.

For a function that models a relationship between two quantities, interpret key features of graphs and tables in terms of the quantities, and sketch graphs showing key features given a verbal description of the relationship. Key features include: intercepts; intervals where the function is increasing, decreasing, positive, or negative; relative maximums and minimums; symmetries; end behavior; and periodicity.

Calculate and interpret the average rate of change of a function (presented symbolically or as a table) over a specified interval. Estimate the rate of change from a graph.
problem_activity: Task
California is in the fifth year of a drought. Towns have been asked to decrease water use across the state. The graph below shows the water storage in Lake Sonoma, a reservoir in Northern California from 1988, shortly after it was first filled, until February 1, 2015.
What questions do you have looking at the graph?
Describe some of the features of the graph.
What might explain these features?  (Consider data collection, weather events and reservoir management decisions.)
Based on the given information, should the region that depends on Lake Sonoma for water use implement additional water conservation measures?
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correct_option_index: 1