H) maintenance (Maintenance) maintenance: editing programs after implementation. Why the need to edit it after use. Why the need to fix the system, there are mainly 2.
G) Maintenance (Maintenance) are maintained. Editing application after use. The reason to modify it after use. Why should fix most of the second verse is.
G) maintenance (maintenance Maintenance) including editing programs after use. Cause to modify the program after use. Why must solve system is mainly 2 number is