Question 17 (1 point) The A horizon in a soil profile is………… (select all that apply) o topsoil o soil material that is approximately parallel to the land surface and contains altered characteristics o deep in the soil profle and lies in a horizontal iayer beneath the bedrock o a zone of mineral lesching Question 18 (1 point) Which of the following soils will have the lowest porosity (lowest pore spacel? o Loamy silt soil o Clay soil o Fine sand soil o Coarse sandy soil Question 19 (1 point) Soil structure describes the arrangements and size of ageregates, which influences. how quickly water will flow in soils o True o False Question 20 (1 point) What are some of the roles hamus plays in soils? (select all that apply) o Increases the amount of topsoil being formed o Increases water infiltration o Increases the amount of minerals and the loss of soil structure o Increases in pore space and aeration