A charged capacitor is discharged through a resistor two times. The time dependence of the logarithm of the discharge current obtained in the two experiments is represented by the two straight lines `1 and 2,` in the figure accompanying the problem. The experimental conditions differed only in one of the three parameters: the initial voltage of the capacitor `U,` the capacitance `C,` or the resistance R. Determine the parameter that was varied in these experiments and in which case this parameter is greater