The author mentions the exact time of the discovery to

answer; the correct answer is (travel horizontally);

radiant energy is a form of kinetic energy only.(a)

d.

thist title points out that you are explaining the nature of the u.s. government. it is the most specific. a representative government consists of a government where decisions are taken according to a voting system. the most essential aspect of a representative government is found in the different structures where voting rights are granted to different groups of people. for example, voting for governor, mayor, president, local police chief etc.