e: \(21\cdot7+21\cdot2-11\left(3^5:3^3\right)\)
\(=21\left(7+2\right)-11\cdot3^2\)
\(=21\cdot9-11\cdot9=9\cdot\left(21-11\right)=9\cdot10=90\)
b: \(15\cdot2^3+4\cdot3^2-5\cdot7\)
\(=15\cdot8+4\cdot9-35\)
=120+36-35
=120+1
=121
d: \(6^3\cdot57+43\cdot6^3\)
\(=6^3\left(57+43\right)=216\cdot100=21600\)
g: \(327-27\cdot\left\lbrack\left(3^3+2020^0\right):7-2\right\rbrack\)
\(=327-27\cdot\left\lbrack\left(27+1\right):7-2\right\rbrack\)
\(=327-27\cdot\left\lbrack\frac{28}{7}-2\right\rbrack=327-27\left(4-2\right)=327-27\cdot2\)
=327-27-27
=300-27
=273
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