The "Karat" marking on jewelry tells you what proportion of gold is mixed with other metals. If 14 parts of gold are mixed with 10 parts of base metal, the combination is called 14-Karat (14K) gold. The higher the Karat rating, the higher the proportion of gold in the object. The lowest Karat gold that can be marketed in the United States is 10-Karat gold. Jewelry does not have to be marked with its Karat quality, but most of it is. If there is a Karat quality mark, next to it must be the U.S. registered trademark of the person or company that will stand behind the mark, as required by the National Gold and Silver Stamping Act.

　　63. If a ring is stamped 24K, it has

　　A. 204 parts of gold.

　　B. 24 parts of gold.

　　C. two and four-tenths parts of gold.

　　D. 10 parts of gold.

　　64. Gold which is 10 Karats in proportion

　　A. represents the highest grade of gold in the U.S.

　　B. cannot be sold in the U.S.

　　C. never carries a Karat quality mark.

　　D. represents the lowest-grade gold marketable in the U.S.

　　65. If gold is marked with a Karat quality mark, it must also

　　A. bear a national gold and silver stamp.

　　B. bear the registered trademark of the entity standing behind the mark.

　　C. bear a "made in the USA" mark.

　　D. bear a percentage mark.

　　66. If the jewelry is marked 14 parts of gold mixed with 10 parts of base metal it will always bear

　　A. a 14K mark.

　　B. a 10K mark.

　　C. an 18K mark.

　　D. a platinum mark.

　　67. This paragraph serves the consumer as

　　A. important buying information.

　　B. a challenge to buy more gold.

　　C. a debate over gold prices.

　　D. advice about buying silver.

　　68. The Stamping Act is

　　A. a regulation for tax.

　　B. rule of law.

　　C. a law that makes such stamping mandate.

　　D. an implement.

　　Questions 69-75 are based on the following passage.

　　Mr. Faugel was convinced that student nervousness had affected their scores; to reduce the anxiety of these students who had already been tested, he gave 22 of them a beta blocker before readministration of the test. Their scores improved significantly. The other 8 students (who did not receive the beta blockers) improved only slightly. Second-time test-takers nationwide had average improvements which were similar to those in Faugel's non-beta blocker group. Beta blockers are prescription drugs which have been around for 25 years. These medications, which interfere with the effects of adrenalin, have been used for heart conditions and for minor stress such as stage fright. Now they are used for test anxiety. These drugs seem to help test-takers who have low scores because of test fright, but not those who do not know the material. Since there can be side effects from these beta blockers, physicians are not ready to prescribe them routinely for all test-takers.

　　69. Where is the only place a person can obtain beta blockers?

　　A. Supermarket

　　B. Convenience store