Organic material provides nitrogen for plants. Which soil component contributes the most nitrogen to plants? • clay
• humus
• sand
• silt

Which statement is a reason to support population regulation? a) it is unethical for us to control birth control rates b) humans have the freedom to produce as many children as desired c) the gap between the rich and poor has been narrowing since 1960 d) billions more people on the earth will intensify many environmental and social problems

In numbering carbon atoms in the parent chain of a hydrocarbon, why would you number from right to left, rather than left to right

What are the similarities of physical and chemical change ?