Final answer:
The maximum resistance when combining a 100 Ohm resistor with a 40 Ohm resistor is the sum of both resistances, which is 140 Ohms.
Step-by-step explanation:
The question pertains to the maximum resistance that can be obtained when combining a 100 Ohm resistor with a 40 Ohm resistor. When resistors are connected in series, their resistances add up. Therefore, the maximum resistance achievable is the sum of the two resistors.
100 Ohm resistor + 40 Ohm resistor = 140 Ohms.
The correct answer is b. 140 Ohms. This is because in a series circuit, the total resistance (Rtotal) is the sum of all individual resistances (R1 + R2 + ... + Rn). Here, it's just R1 + R2, which equals 100 Ohms + 40 Ohms.