A 1 Kw signal is transmitted using as communication channel which provides attention at the rate of $-2 dB$ per km. If the communication channel has a total length of 5 km , the power of the signal received is [ gain in $dB = 10 log \bigg( \Large\frac{P_0}{P_c}\bigg) ]$

Question

$\begin{array}{1 1} 900\;w \\ 100\;w \\ 990\;w \\ 1010\;w \end{array}$