How to set permissions for the following scenarios? i. You can modify a file but cannot delete it. ii. You can see the file names (directory content) but you cannot read their contents or modify them.
a. i. Change file permissions to read-only, ii. Change directory permissions to read-only.
b. i. Grant write permission only, ii. Grant read permission only.
c. i. Grant write permission only, ii. Revoke read permission.
d. i. Grant read and write permission, ii. Revoke read and write permission.