When a charged capacitor is connected to earth, it discharges and the voltage V across it will decrease according to the equation:
dV/dt = -V/RC
where R (the resistance) and C (the capacitance) are constants. If the voltage V across a certain capacitor with capacitance C = 3 x 10-6 farads drops from 10 volts to 1 volt in two seconds, determine the resistance R.