Calculați:
Dau coroană plss urgentt +10 puncte

[tex]a)(12 \times \frac{5}{12 } + 1 \times \frac{2}{3} - 3 \times \frac{5}{6} + 2\times \frac{3}{4} ) \div (2 \times \frac{1}{2} \times \frac{2}{5} - \frac{7}{9} ) = [/tex]
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