(3)-3-4+ 19- 1 1; (4)-8+ 12- 16-23.

2. Calculation:

( 1)-4.2+5.7-8.4+ 10; (2)6. 1-3.7-4.9+ 1.8;

3. Calculation:

( 1)(-36)-(-25)-(+36)+(+72); (2)(-8)-(-3)+(+5)-(+9);

(3) ; (4)-9+(-3 )+3 ;

[-|98|+76+(-87)]*23[56+(-75)-(7)]-(8+4+3)

5+2 1*8/2-6-59

68/2 1-8- 1 1*8+6 1

-2/9-7/9-56

4.6-(-3/4+ 1.6-4-3/4)

1/2+3+5/6-7/ 12

[2/3-4- 1/4*(-0.4)]/ 1/3+2

22+(-4)+(-2)+4*3

-2*8-8* 1/2+8/ 1/8

(2/3+ 1/2)/(- 1/ 12)*(- 12)

(-28)/(-6+4)+(- 1)

2/(-2)+0/7-(-8)*(-2)

( 1/4-5/6+ 1/3+2/3)/ 1/2