How can you know if the person or organization providing the information has the credentials and knowledge to speak on this topic? One clue is the type of web site it is--the domain name ".gov" tells you that this is a government web site. Listen to the podcast again. Who is being interviewed?

Who is being interviewed

Explanation: Who is being interviewed tells us if the person being interviewed has the credentials to speak on the particular topic. An example is Having a doctor in a health show or program discuss about Cancer. Because he is a medical doctor we can confirm he has the expertise and required knowledge required for the topic. How to recognize the person being interviewed doesn't have the credentials is having a Mechanical Engineer discuss (Cancer) his field of profession has more to do with engine's so he isn't the right person to have on such delicate topic.

answer; the population in brazil is very diverse there are many races and ethnic groups