If transmission power of a surface is $\frac{1}{9}$, reflective power is $\frac{1}{6}$, then what is its absorptive power?
A$\frac{18}{13}$
B$\frac{13}{18}$
C$\frac{3}{15}$
D$\frac{15}{3}$
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B$\frac{13}{18}$
b (b)
$t+r+a=1$
$a=1-(t+r)$
$=1-\left(\frac{1}{9}+\frac{1}{6}\right)$
$a=\frac{13}{18}$
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