1. 计算:
(1)$(-1.25)×(-2.5)×(-5)×(+2)×(-4)×(-8);$
(2)$(-\dfrac{2}{7})×0.2×(-\dfrac{7}{4})×(-10);$
(3)$(-13)×(-124)×\dfrac{1}{13}×(-\dfrac{1}{62});$
(4)$(-0.25)×32×0.125×(-\dfrac{3}{4}).$

(1)原式$=-(1.25×8)×(2.5×4)×(5×2) =-10×10×10=-1000.$
(2)原式$=[(-\dfrac{2}{7})×(-\dfrac{7}{4})]×[0.2×(-10)]=\dfrac{1}{2}×(-2)=-1.$
(3)原式$=-(13×\dfrac{1}{13})×(124×\dfrac{1}{62})=-1×2=-2.$
(4)原式$=(-0.25×4)×(0.125×8)×(-\dfrac{3}{4})=1×1×\dfrac{3}{4}=\dfrac{3}{4}.$

2. 计算:
(1)$( \frac{2}{3} - \frac{5}{6} + \frac{1}{12} - \frac{7}{8} ) × (-24);$
(2)$\frac{7}{13} × (-9) + \frac{7}{13} × (-18) + \frac{7}{13};$
(3)$-3.14 × 35.2 + 6.28 × (-23.3) - 1.57 × 36.4;$
(4)$( \frac{3}{4} - \frac{5}{6} - \frac{1}{8} ) × 24 - 3.42 × 3 - 6.58 × 3.$

(1)原式$=\dfrac{2}{3}×(-24)-\dfrac{5}{6}×(-24)+\dfrac{1}{12}×(-24)-\dfrac{7}{8}×(-24)=-16+20-2+21=23.$
(2)原式$=\dfrac{7}{13}×(-9-18+1)=\dfrac{7}{13}×(-26)=-14.$
(3)原式$=-3.14×35.2+3.14×(-46.6)-3.14×18.2=-3.14×(35.2+46.6+18.2)=-3.14×100=-314.$
(4)原式$=\dfrac{3}{4}×24-\dfrac{5}{6}×24-\dfrac{1}{8}×24-3×(3.42+6.58)=18-20-3-3×10=18-20-3-30=-35.$