What is 10 log (0.003/10^-12)

$$\\10 log (0.003/10^{-12})\\
\\=10log(0.003*10^{12})\\\\
=10log(3*10^{-3}*10^{12})\\\
=10log(3*10^{9})\\\\
=10[log3+log10^9)\\\\
=10log3+90log10\\\\
=10log3+90\\\\
=90+10log3$$

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