At T(K) the $K_c$ for the reactions (I) and (II) are $2.4 \times 10^{30}$ and 1.4 respectively. What is the $K_c$ value for: $\frac{1}{2}N_2(g) + \frac{1}{2}O_2(g) + \frac{1}{2}Br_2(g) \rightleftharpoons NOBr(g)$?
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When reversing a reaction, $K$ becomes $1/K$; when multiplying coefficients by $n$, $K$ becomes $K^n$.