1. The problem statement, all variables and given/known data A primary energy source is able to provide 0.7 Watts power in order to charge a mobile telephone battery pack. The telephone operates at 3.5 V, and the mobile telephone’s 3.5 V battery pack has a capacity of 1050mAh. In “talk” the mobile phone draws an average current from its battery of 100mA. (i) How many minutes of talk time will this battery pack provide, at the average current for “talk”? 2. Relevant equations P=0.7 I=100mA V=3.5V 3. The attempt at a solution Now i'm not sure what formula to use in order to find time. Can someone help me?