$\text{1d)2².3-($1^{10}$ +8):3²}$
$\text{=4.3-(1+8):9}$
$\text{=12-9:9}$
$\text{=12-1}$
$\text{=11}$
$\text{e)6²:43+2.5²}$
$\text{=36:43+2.25}$
$\text{=$\frac{36}{43}$+50}$
$\text{=50 $\frac{36}{43}$}$
$\text{f)2007.75+25.2007}$
$\text{=2007.(75+25)}$
$\text{=2007.100}$
$\text{=200700}$