There are four amendments to the constitution about who can vote

Amendment XXVI - Right to Vote at Age 18 (1971),  Amendment XIX - Women's Right to Vote (1920),    Amendment XV - Rights Not to Be Denied on Account of Race (1870)

Explanation:

answer; /// the answer to the first question is (b) it began when people first deliberately seeds; /// and (d); // it gave people a steady food supple for the first time;

answer; i believe that the correct answer is (scientific approach)