( /=division) ( * =multiplier)
A= -2/21 * 14/5 - 8/5
= -2*7*2 / 7*3 * 5 - 8/5
= -4/15 -8/5
= -4/15 - 24/15
= -28/15
B = 1/4 - 5/24
= 6/ 24 - 5 /24
= 1/24
C= -4/3 + 14/30
= -40/30 + 14/30
= - 26/ 30
D= (8/15 - 7/5) * (-1/6 + 2/9)
= (8/15 - 21/15) * (-1*3 / 6*3 + 2*2 / 9*2)
= -13/15 * 1/18 = -13 / 270