Решение:
a) \[ -9 \cdot 13 = -117 \]
б) \[ -76 : (-19) = 4 \]
в) \[ 0.6 \cdot (-3.4) = -2.04 \]
г) \[ -7\frac{4}{5} \cdot (-\frac{11}{15}) = -\frac{39}{5} \cdot (-\frac{11}{15}) = \frac{39 \cdot 11}{5 \cdot 15} = \frac{13 \cdot 11}{5 \cdot 5} = \frac{143}{25} = 5\frac{18}{25} = 5.72 \]