A time-series graph displays the price of copper. The slope of the line is negative for periods when the
A) price of copper is rising.
B) price of copper is low and not changing.
C) price of copper is falling.
D) quantity of copper is falling.

Question

Quizplus · Accepted Answer

The slope of a line on a time-series graph represents the rate of change over time. Therefore, a negative slope indicates that the price of copper is decreasing over time, which would correspond to option C, when the price of copper is falling.

A Time-Series Graph Displays the Price of Copper