\[\boxed{\mathbf{796}\mathbf{.}}\]
\[1)\ln 81 = 4,39444\ldots \approx 4,3944\]
\[2)\ln 2 = 0,69314\ldots \approx 0,6931\]
\[3)\ln{0,17} =\]
\[= - 1,77196\ldots \approx - 1,7719\]
\[4)\ln\frac{6}{7} =\]
\[= - 0,15415\ldots \approx - 0,1542\]