a$.$ What is the three bit permission value which represents permission to write

$($but not read or execute$)$ a file? What is the corresponding octal digit $(0-7)$ for

these permissions?

b$.$ What is the three bit permission value which represents permission to read

and write $($but not execute$)$ a file? What is the corresponding octal digit $(0-7)$

for these permissions?

c$.$ What is the three bit permission value which represents no permission to

perform any operation $($read$,$ write, or execute$)$ on a file? What is the

corresponding octal digit $(0-7)$ for these permissions?