Why must you avoid contamination of the peat by either younger living plant roots or older dead carbon such as limestone or oil spills

Did you know it's illegal to own only one guinea pig in switzerland?   : )

He want to contact the red cross/red crescent because they are the main non profit organization that deals with disasters around the world 

The answer is c, i, iii, and iv. this is because farming and mining deal with harvesting raw materials, construction work falls under manufacturing, and piloting a plane is a service. ii is wrong because making bread is using  raw materials to produce goods, which would fall under the secondary sector, not primary.