【单选题】A man-made chemical that attracts male gypsy moths by duplicating the natural attractant of female gypsy moths has been patented as No. 3,018,219. Dr. Martin Jacobson of Silver Spring, Md., assigned p...
【单选题】It is helpful to illustrate these points by looking at the case of the United States, precisely because 3.__________. Coal, copper, iron, silver, and nickel are just a few of the natural resources the...
A.
countries need to - or choose to import at least some goods and services
B.
different countries have comparative advantages on different products
C.
exports are also more than just an outlet for “ excess ” production
D.
it has the capability of producing the goods or supplying the services
E.
it comes closer to being self-sufficient than most other countries
F.
sell goods or services to other countries at prices higher than the prices