Two gray surfaces that form an enclosure exchange heat with one another by thermal radiation. Surface 1 has a temperature of 400 K, an area of 0.2 m², and a total emissivity of 0.4. Surface 2 has a temperature of 600 K, an area of 0.3 m², and a total emissivity of 0.6. If the view factor F₁₂ is 0.3, the rate of radiation heat transfer between the two surfaces is
(a) 135 W

(b) 223 W

(c) 296 W

(d) 342 W

(e) 422 W