Why did the runways have to be constantly repaired?

like this::

Explanation:

The RRR process has developed into five stages: 1) damage assessment, 2) Minimum Operating Strip (MOS) selection, 3) Explosive Ordinance Disposal (EOD), 4) bomb damage repair, and 5) MOS set-up.

Because it needed mantainece

Explanation:

in which two ways were the northeast woodland indians and the southeast indians similar? both collaborated to form the iroquois confederacy. both cultivated the crops of corn, beans, and squash. both lived in rich environments of swamps and rivers. both lived in tree-bark dwellings called wigwams. both expected men to hunt, while women farmed.