Electronic flash units for cameras contain a capacitor for storing the energy used to produce a flash. In one such unit the flash lasts for 0.00129 s with an average light power output of 1,657 W. If the conversion of electrical energy to light is 95% efficient (the rest of the energy goes to thermal energy), what is the capacitance? Assume the camera batteries can create a potential difference of 12 V between the capacitor plates. (answer in F.)