помогите математика​

2) (-4 1/5 * 1,3) = - 21/5 * 13/10 * 10/13 = -4 1/5

3) (-5 6/7 * 3/13) * (- 4 1/3) = 41/7 * 3/13 * 13/3 = 5 6/7  

4) -( 7 5/12 + 7/36) * 5 1/7 = - (7 5/12 * 5 1/7 + 7/36 = 5 1/7)