Which of these is a source for particulate matter in the air?
a. automobiles
b. dust
c. fires
d. all of the above

If birth rates fall below the replacement level, then a country is in which stage of demographic transition? a. urbanization/industrialization b. mature industrial c. postindustrial d. pre-modern

Which characteristic do healthy families have in common? a. having above average household income b. ignoring one another’s happiness c. demonstrating love for oneself d. communicating with one another

If gonorrhea is a treatable infection why do so many men experience severe damage and even in infertility or joint infections as a result of leaving it untreated