$\text{A.}$ $\int_0^{+\infty} x^2 \mathrm{e}^{-x^2} \mathrm{~d} x$ ．
$\text{B.}$ $\int_0^{+\infty} \frac{1}{\sqrt{x} \mathrm{e}^x} \mathrm{~d} x$ ．
$\text{C.}$ $\int_0^{+\infty} \frac{1}{x \ln ^2 x} \mathrm{~d} x$ ．
$\text{D.}$ $\int_1^{+\infty} \frac{1}{(x+1) \ln ^2(x+1)} \mathrm{d} x$ ．
$\text{E.}$
$\text{F.}$