Which of the following is an example of a scale on a map?
a. 1: 12,000
c. an arrow pointing north
d. an explanation of the symbols used?

Answera discharge of static electricity;

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.

The correct answer is:   [b]:   "physical systems" .