Answer:
Overgrazing by livestock is leading to significant environmental degradation—Grevy's zebras compete with the ever-increasing livestock population and agricultural crops for water.
Explanation:
Human history and prehistory
: <span>Only about 2.8 million were drafted under the Selective Service System
All males aged 21 to 30 were required to register for military service for a service period of 12 months. As of mid-November 1917, all registrants were placed in one of five new classifications. Men in Class I were the first to be drafte and men in lower classifications were deferred. Dependency deferments for registrants who were fathers or husbands were especially widespread.[9] The age limit was later raised in August 1918 to a maximum age of 45. The military draft was discontinued in 1920
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