Table: ar10
Columns: name_designation
year_of_introduction
country_of_origin
primary_cartridge
primary_user

Question: If the country of Origin is South Africa, who is the primary user?
SQL: SELECT "primary_user" FROM ar10 WHERE "country_of_origin" = 'South Africa'

Question: If the Country of Origin is Denmark and the year of introduction is 1962, what is the primary cartridge?
SQL: SELECT "primary_cartridge" FROM ar10 WHERE "year_of_introduction" = '1962' AND "country_of_origin" = 'Denmark'

Question: How many different years was the name/designation cetme?
SQL: SELECT COUNT("year_of_introduction") FROM ar10 WHERE "name_designation" = 'CETME'

Question: If the country of origin is switzerland, what is the name/ designation?
SQL: SELECT "name_designation" FROM ar10 WHERE "country_of_origin" = 'Switzerland'