$(40$ pts$)32-$bit FPN $($IEEE $754)$ to decimal and back $($Need to show all steps$)$

$($a$)$ Convert the following $32-$bit FPN $($IEEE $754)$ to decimal number:

$11000000011001000000000000000000$

$($b$)$ Convert the following decimal number to $32-$bit FPN $($IEEE $754)$ number:

$(-3\mathrm{.}125{)}_{10}$