What do these items have in common?

trees, contouring, terraces

rice farming
architecture
erosion control
paper manufacturing

erosion control

Explanation:

Erosion is caused by a physical agent such as water, air or other. This results in the removal of the top layer of the soil.

Trees, terraces, contouring will control erosion. These will reduce the soil erosion by holding the soil.

really dont know just need some points

hydroxyl -oh

alcohols, always polar, can form hydrogen bonds with h2o molecules

carboxyl -cooh  

cargoxylic acids, has acidic properties which is a source of hydrogen ions, found in cells in ionized for with a charge of oh-1

carbonyl > co

ketone if within skeleton, aldehyde if group is at the end of skeleton, k & a may be structural isomers, it determines 2 sugars (ketose & aldose)

amino -nh2

amines, acts as a base, it can pick up h+ ions from surrounding solution, ionized with charge of 1+

methyl ch2

addition to rna/dna affects and gene expression

phosphate -opo3 ²⁻

organic phosphates, contributes to negative charge to, molecule that it is a part of, and potential to react with h20

sulfhydryl -sh

thiols, cross-linking stabilize the protein, and it is structure