tolong jawab ya kak mohon menghunakan caranya

a) 2/5 × 5/6 = 1/3
b) (2/5×1/2):5/6= 1/5:5/6= 1/5×6/5= 6/25
c) 2/5×5/6 - 2/5×1/2= 1/3 - 1/5= 5/15-3/15= 2/15
d) (5/6-1/2)×2/5= (5/6-3/6)×2/5= 2/6 × 2/5= 4/30= 2/15
e) (2/5+5/6):(2/5-5/6)= (12/30+25/30):(12/30-25/30)= 37/30:(-13/30)= 37/30×(-30/13)= -37/13
f) (5/6-2/5):(5/6+2/5)= (25/30-12/30):(25/30+12/30)= 13/30:37/30= 13/30×30/37= 13/37