4. A rechargeable flashlight battery is capable of delivering 85 mA for about 12 h. How much charge can it release at that rate If its terminals voltage is 1.2 V how much energy can the battery deli?

To find the total charge the battery can release, use the formula ( Q = I \times t ), where ( I = 85 , \text{mA} = 0.085 , \text{A} ) and ( t = 12 , \text{h} = 43,200 , \text{s} ). Thus, ( Q = 0.085 , \text{A} \times 43,200 , \text{s} = 3,672 , \text{C} ). To calculate the energy, use ( E = Q \times V ), where ( V = 1.2 , \text{V} ). Therefore, ( E = 3,672 , \text{C} \times 1.2 , \text{V} = 4,406.4 , \text{J} ).