3.why, according to this report, did the u. s. economy change in the 1980s?

The reason that the U.S economy change in the 1980s is because of Reagan's economic policy. In early 1980s, Reagan imposed various economic tax cut for the people , thinking that it would be good, but the government faced various financial problems instead and America went to recession in 1982

Phloem is the vascular tissue that takes carbohydrates to other parts of the plant