A fixed conducting channel needs several voltage rows to show the current law. Exact arithmetic here means exact results for the stated model inputs; measured inputs still carry uncertainty and significant-figure limits.
highlighted = computed this step
One volt gives two amps through the conducting channel
Hold conductance at 2 S. Voltage 1 V gives current 2 A.
I=GV=2S⋅1V=2A
Two volts doubles the current
The same conductance with voltage 2 V gives current 4 A. Voltage is the changed source factor.
I=GV=2S⋅2V=4A
Four volts makes the voltage-to-current line clear
Voltage 4 V gives current 8 A. The channel is ideal and ohmic here; noise and gating kinetics belong in later instrument lessons.