The gas discharge tube lights up at a voltage of 2 kV. At the same time, its resistance drops sharply, and to maintain the rated current of 40 mA, it is necessary to connect a ballast resistor in series with the tube. Resistors R of 100 kohms are available, designed for a power of 10 watts. How many such resistances are needed and how should they be connected to provide the required amount of operating current? The resistance of the tube in the ignited state and the internal resistance of the current source can be neglected.

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