8. 计算:
(1) $(-6)÷(-3)$;
(2) $(-18)÷6$;
(3) $(-4)÷(-2)$;
(4) $-2÷\frac{1}{2}$;
(5) $(-6)÷(-\frac{1}{3})$;
(6) $-\frac{1}{2}÷\frac{1}{4}$;
(7) $48÷(-6)$;
(8) $(-\frac{1}{2})÷(-3)$;
(9) $-1.25÷(-\frac{1}{4})$;
(10) $-\frac{3}{8}÷(-\frac{9}{16})$;
(11) $-\frac{5}{6}÷\frac{1}{3}$;
(12) $(-27)÷9$;
(13) $(-\frac{9}{25})÷(-\frac{3}{10})$;
(14) $1÷(-9)$;
(15) $0÷(-7)$;
(16) $\frac{4}{3}÷(-1)$;
(17) $-0.25÷\frac{3}{4}$;
(18) $(-\frac{3}{4})÷2\frac{2}{3}$;
(19) $7÷(-1\frac{1}{6})$;
(20) $8\frac{2}{15}÷(-2)$.

8. (1)2 (2)-3 (3)2 (4)-4 (5)18
(6)-2 (7)-8 (8)$\frac{1}{6}$ (9)5 (10)$\frac{2}{3}$
(11)$-\frac{5}{2}$ (12)-3 (13)$\frac{6}{5}$ (14)$-\frac{1}{9}$
(15)0 (16)$-\frac{4}{3}$ (17)$-\frac{1}{3}$ (18)$-\frac{9}{32}$
(19)-6 (20)$-\frac{61}{15}$