The rate at which water evaporates from a certain reservoir depends on the air temperature. The table below shows the number of acre-feet (af) of water per day that evaporate from the reservoir for various temperatures in degrees Fahrenheit.
Temperature, °F af
40 760
60 1600
70 2020
85 2650
(a) Find a linear model for the number of acre-feet of water that evaporate as a function of temperature.
E(T) = 1
(b) Explain the meaning of the slope of this line in the context of this problem.
The value of the slope means that an additional 1 af evaporate for a 42° increase in temperature.
The value of the slope means that an additional 42 af evaporate for a 1° increase in temperature.
The value of the slope means that an additional 1 af evaporate for a 42° decrease in temperature.
The value of the slope means that an additional 42 af evaporate for a 1° decrease in temperature.
(c) Assuming that water continues to evaporate at the same rate, how many acre-feet of water will evaporate per day when the temperature is 75°F?
3 af