What are two environmental challenges that Texas faces in the 21st century? What are some of the proposed solutions to those challenges.

i think the answer is c, rivers.

explanation:

sometimes, borders fall along natural boundaries like rivers or mountain ranges. for example, the boundary between france and spain follows the crest of the pyrenees mountains. for part of its length, the boundary between the united states and mexico follows a river called the rio grande. the borders of four countries divide africa’s lake chad: niger, chad, cameroon, and nigeria.

under god i have placed my chiest strentgh and the safe guard to my loyal subjects

to replace ineffective because   andrew jackson's spoil system was a deliberate policy after he became president to remove federal employees he considered to be political opponents and replace them with his own supporters.