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Courtney is going on a road trip. The function $f(t)$ measures the amount of fuel Courtney’s car has consumed (in gallons) where $t$ is measured in hours since Courtney left her hometown. Which statement best explains the meaning of $f'(5)=2.5$?

Five hours since Courtney left her hometown, Courtney’s car has consumed 2.5 gallons of fuel. Over the five hours since leaving her hometown, the amount of fuel consumed by Courtney’s car increased by 2.5 gallons every hour. Five hours after purchase, the amount of fuel consumed by Courtney’s car will increase by 2.5 gallons over the next hour. As time increases by a very small amount from 5 hours, the amount of fuel consumed by Courtney’s car increases by 2.5 times as much as the change in time. The instantaneous rate of change of the amount of fuel consumed with respect to time 5 hours since leaving her hometown is 2.5 gallons per hour.