From the reaction above, the rate is given by the following formula: r = -(1/2) dA / dt = - dB / dt = (1/3) dC/ dt Note that A and B charge is negative due to they decrease with time given dA / dt = -0.110 M/s hence dB / dt = -0.110 / 2 = -0.055 M/s dC / dt = (-3/2) (-0.110) = 0.165 M/s
If you increase the frequency, the photon will have more energy and can therefore transfer more electrons to the other side. As such, you will have an increased current.