In the circuit shown in the figure, the power supply voltage remains unchanged. When the switches S1, S3 are closed and S2 is disconnected, the current representation is 1.8A. When S1 is closed and S2, S3 is disconnected, the current representation is 0.6, A. when S2 is closed and S1, S3 is disconnected, the power consumed by R2 is 1.6W, The range of 2.5 a sliding rheostat ammeter is 0-0.3a. When S1 and S3 are closed and S2 is disconnected, what is the minimum resistance in the sliding rheostat access circuit

In the circuit shown in the figure, the power supply voltage remains unchanged. When the switches S1, S3 are closed and S2 is disconnected, the current representation is 1.8A. When S1 is closed and S2, S3 is disconnected, the current representation is 0.6, A. when S2 is closed and S1, S3 is disconnected, the power consumed by R2 is 1.6W, The range of 2.5 a sliding rheostat ammeter is 0-0.3a. When S1 and S3 are closed and S2 is disconnected, what is the minimum resistance in the sliding rheostat access circuit

1 R2 = 10 Ω
2 U=6V
3 R min ≈ 3.3 Ω
PS: I really don't want to write the process. I'll give you the answer first. In other words, this is also the homework assigned by our teacher. What I did myself may not be right. Please refer to it