Practice Questions $($Be careful when using calculator$)$:

$((2$&$49)-4^2-(3\backslash$times $7+9)-$:$5)/(10\backslash$times $2^(-2))=\_\_\_\_\_\_\_\_\_\_\_\_$

$5\mathrm{.}8/(3\mathrm{.}2\backslash$times $10^(-4))=\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$

$(42$ x $3)-17$ x $23=\_\_\_\_\_\_\_\_\_\_\_\_$

$42$ X $(3-17)$ x $23=\_\_\_\_\_\_\_\_\_\_\_\_$

$42/(3-17)\backslash$times $3^3=\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_$

$(3+2)63-25=\_\_\_\_\_\_\_\_\_\_\_\_\_\_$

$(3+2)63-$: $25=\_\_\_\_\_\_\_\_\_\_\_\_\_\_$