a: =8-5+12x4
=3+48
=51
b: \(=5\cdot\left[80:8+90\right]-50=5\cdot100-50=450\)
c: \(=2\left[\left(7-3\right):4+99\right]-100\)
\(=2\cdot100-100=100\)
d: \(=2^5+5\cdot2^4-3\cdot2^5\)
\(=32-96+80=16\)
e: \(=\dfrac{3^{12}}{3^{10}}+5\cdot16-49=9-49+80=40\)