Problem 12-58 Resistor network - C

In the Figure, what is the
(a) current through the $150 \Omega$ resistor?
(b) potential difference across the $250 \Omega$ resistor?
(c) current through the $350\Omega$ resistor?
(d) potential at $\text{point A}$ (assuming zero potential at the negative terminal of the battery)

[Ans. (a) $0.057 \;A$   (b) $14 \;V$   (c) $0.035\; A$  (d) $21 \;V$ ]

Correct! These two form a parallel pair of resistors.

If the equivalent resistance of this pair is $R'$ then which expression gives $R'$ ?

(A)   $1/R' = 1/350 + 1/550$

(B)    $R' = 350 + 550$