Please help me with this

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.

The graph describes the motion of an object. the object moves with from a to b. it from b to c. it moves with from c to d.

Which lists the pairs of plates in order from least to greatest in terms of the work done to move the electron?