28√15√8+(2√15-7√8)^2=28√120+(2√15)^2-2*2*7√15√8+(7√8)^2=
<span>=28√120+4*15-28√120+49*8=60+392=452</span>
631 259 + 7000 =638 259
21 009 + 7000 = 28 009
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3 259 + 10 = 3269
89005 + 10 = 89 015
777016+10 =777 026
..........................
13т 427кг просто и понятно