Calculati:
a) (-3/10+4/15) x 2 1/2
b) (-7/30+1/12) x (-5/6)
c) (-9/28+11/42) x (-2 2/5)
d) (-18) x (-5/24+7/36)
e) (-1 4/5) x (-2/9+1/12)
f) 4/9 x (-2/3+5/6)
Please help