Can someone answer these few questions there all about the galapagos asap

Starting with only the balmer series light (visible light), how could we ensure that the solar panels generate a current that mark can use for his power station? a)by gradually increasing the brightness (amount) of light that we shine on it. b)by gradually increasing the frequency of the light we shine on it. c)by gradually increasing the wavelength of the light that we shine on it.

Give an example in which the electrical energy changes to light energy

The voltage applied across a given parallel-plate capacitor is doubled. how is the energy stored in the capacitor affected?