Why was the grand canal such an essential part of china's economic health?
a. it to stop flooding of the hwang he and therefore allow for more food production
b. it was a practical and economic way to transport foods like rice from the yangzi river valley to residents of northern regions
c. it allowed otherwise unemployed chinese laborers to earn a living wage and support their families
d. it allowed luxury goods to move quickly to port markets on the yellow sea

abraham lincoln  (february 12, 1809  – april 15, 1865) was an american statesman, politician, and lawyer who served as the 16th  president of the united states  from 1861 until  his assassination  in april 1865. lincoln led the nation through the  american civil war, its bloodiest war and its greatest moral, constitutional, and political crisis.[2][3]  he preserved the  union,  abolished slavery, strengthened the  federal government, and modernized  the u.s. economy.

i dont know the answer sorry but if i knew it i would of told you