a: \(\left(-11\right)\cdot\left(-28\right)+\left(-9\right)\cdot13\)
\(=11\cdot28-9\cdot13\)
\(=308-117=191\)
b: \(\left(-69\right)\left(-31\right)-\left(-15\right)\cdot12\)
\(=69\cdot31+15\cdot12\)
\(=180+2139=2319\)
c: \(\left[16-\left(-5\right)\right]\cdot\left(-7\right)=\left(16+5\right)\cdot\left(-7\right)\)
\(=-7\cdot21=-147\)
d: \(\left[\left(-4\right)\left(-9\right)-6\right]\left[\left(-12\right)-\left(-7\right)\right]\)
\(=\left[36-6\right]\left[-12+7\right]\)
\(=-5\cdot30=-150\)
[11].[-28]+[-9].13=191; [-69].[-31]-[-15].12=25848
[16-[-5]].[-7]=-147; [[-4].[-9]-6].[[-12]-[-7]]=115
