Use suitable propertiesa.1/3 (-2/5)×3/5 3/5×-2/5b.1/6×3/8-4/5 1/6×-2/8

Use suitable properties
a.1/3 (-2/5)×3/5 3/5×-2/5
b.1/6×3/8-4/5 1/6×-2/8
c.9/7-3/5 1/4×2/7-2/7×5/13