$(30$ points, submit on paper in class$)$ For each of these structure definitions, show the relative offset in bytes of each structure member for both the unpacked $($default alignment$)$ and packed cases. Also show the size of the structure in bytes. For each, write the structure definition with the offsets and total size $($in bytes$)$ next to the corresponding fields like this example:

offsets

structure s unpacked packed

char a; $0$

int $b$;$,4$

char c; $8$

short d; $,10,6$

$\}$;

$128$ size of structure in bytes

$($a$)$

struct student $\{$

char first $[15]$;

char last $[15]$;

double gpa;

int creditHours;

$\}$;

$($b$)$

struct course $\{$

char dept $[5]$ ;

short number $[5]$ ;

char section $[4]$;

int enrollment;

$\}$;