The capacity of batteries such as the typical AA alkaline battery is expressed in units of milliamp-hours (mAh). An "AA" alkaline battery yields a nominal capacity of 2850 mAh.
The starting voltage of a fresh alkaline battery is 1.45 V. The voltage decreases during discharge and is 0.75 V when the battery has delivered its rated capacity. If we assume that the voltage declines linearly as current is withdrawn, estimate the total maximum electrical work the battery could perform during discharge.