Social scientists who gauge economic and social progress may rely on research by accessing available data such as stock market prices, unemployment rates, and statistics on health and welfare.

secondary data

Explanation: Secondary data research is usually employed by social scientists in gauging economic and social progress. This they carry out by accessing available data such as stock market prices, unemployment rates, and statistics on health, welfare and so on. Secondary data research or analysis is one that was collected by another individual for a different primary purpose other than the one being carried out and thusly these existing data provides a viable option for researchers, scientists, analysts etc. who may have the required time and resources to carry out primary data analysis.

c

explanation: because you need to reduce the pollution on land,the exhaust fumes will stop,and stop it in water,the oil that is in the oceanharms the fish   sorry if you   have been waiting long