a) $$ \sqrt{0.0036} + \sqrt{25} = 0.06 + 5 = 5.06 $$
б) $$ 3 \times \sqrt{1.21} = 3 \times 1.1 = 3.3 $$
в) $$ \sqrt{400} \times \sqrt{81} = 20 \times 9 = 180 $$
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