A9 v battery is connected in series to four resistors as follows: r1 = 2 ω, r2 = 4 ω, r3 = 4 ω, and r4 = 8 ω. what is the total resistance of the circuit?
a. 0.5 ω
b. 9 v
c. 18 a
d. 18 ω

Since the four resistance are connected in series, the total resistance is sum of individual resistances.
Total resistance= R1+R2+R3+R4 = (2+4+4+8)Ω = 18Ω
18 A is not the answer because A stamds for Ampere whivh is SI unit of electric current.
Answer is option d

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