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Verified answer

1.

-2.86+7.004-4.144=0

2.

-6.036/0.503+12(2/3)=-12+12(2/3)=2/3

3.

9

4.

2300*1.1=2530

5.

75.3-5.015=70.285кг

6.

3.5+4.86/0.3=3.5+16.2=19.7

7.

3+4=7

28/7=4

4*3=12 мальчиков