Tính bằng cách hợp lý nếu có

Tính bằng cách hợp lý nếu có:
a) $\frac{15}{16}:{\left(\frac{1}{2}-\frac{2}{3}\right)}^2$
b) $\frac{15}{34}+\frac{7}{21}+\frac{19}{34}-1\frac{15}{17}+\frac{2}{3}$​
c) $35\frac{1}{6}:\left(\frac{-4}{5}\right)-45\frac{1}{6}:\left(\frac{-4}{5}\right)$​ 
d) $\frac{3}{4}-\left[\left(-\frac{5}{3}\right)-\left(\frac{1}{12}+\frac{2}{9}\right)\right]$​
e) $-3,75. (-7,2)+2,8 . 3,75$​
f)  $2^3.\left(0,75-\frac{1}{4}\right):\left(3\frac{1}{2}-2\frac{1}{4}\right)$​
g) $\left(3\frac{1}{2}+0,25\right)-\left(\frac{1}{4}-3,25+\frac{1}{2}\right)$
h)  $0,1\sqrt{225} - \sqrt{\frac{1}{4}}$​
i) $\frac{{(-2)}^{10}. 3^{31}+ 2^{40}.{(-3)}^6}{{(-2)}^{11}. {(-3)}^{31}+ 2^{41}.3^6}$​