In a crushing plant, stones are broken down into gravel using crushers. the gravel is used mostly for water filtration and in landscaping. the density of the gravel particles is the same as the density of the stone from which they are made. why does the density not change?

Increasing the release of greenhouse gases and pollution

Answer(a); // soil salinization and waterlogging;

Earthquake waves that vibrate from side to side and up and down only through solids are known as "seismic waves."hope my answer has you : )

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.