Is the use of sound waves to detect and measure objects underwater. a. gps b. ostm c. sonar d. gis

It's option C. Sonar.

The answer is c) people evacuated but almost all returned

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.