How was Greenland formed? 

From a volcano  i guess  i have not had geography yet 

Part of Greenland was formed by ice glaciers

Answer (true);

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.