a, 20 : 2^2 . 14 = 20 : 4 . 14 = 5 . 14 = 70
b, 64 : 2^5 . 30. 4 = 64 :32 . 30 . 4=2 . 30 . 4 = 60 . 4 = 240
c, 2^2 . 3^2 - 5.2.3 = 4. 9 - 30 = 36 - 30 = 6
d, 3^2 . 5 - 2^2 . 7 + 1.5 = 9 .5 - 4 .7 + 1.5 = 45 - 28 + 5 = 22
e, 5^2 . 2^3 + 3^2 .7 -8^2 .2 =25 . 8 + 9 .7 - 64.2 =200 + 63 - 128= 135
f, (6.5^2 - 13.7).2 - 2^3.(7+3)= (6.25 - 13.7).2 - 8.(7+3) = (150-91).2 - 8.(7+3)=59.2 - 8.10= 118-80=38