Answer:
1. "Both countries would lose their land. It contributed to manifest destiny because now the US finished off getting lands in the West, from sea to shining sea."
2. "Northern Whigs feared that war with Mexico would result in the United States gaining new territories in the southwest, which would encourage the expansion of slavery."
3."From sea to shining sea was originally used in the charters of some of the English Colonies in North America, is an American idiom meaning "from the Atlantic Ocean to the Pacific Ocean"
4. "With its triumph in the Mexican-American War, the United States seemingly realized its Manifest Destiny by gaining an immense domain (more than 525,000 square miles of land), including present-day Arizona, California, western Colorado, Nevada, New Mexico, Texas, and Utah."
Explanation: These are all from the internet so you might wanna swap them around.
