Which of the following statements is true about patents and copyrights?
举一反三
- Which of the following statements is true about patents and copyrights? A: They have benefits and costs. B: They lead to higher prices. C: They enhance the ability of monopolists to earn above-average profits. D: They lead to lower prices.
- Which of the following statements about Milton are true?
- Which of the following statements is NOT true about the lead?
- Which of the following statements about the heart is true?
- Which of the following statements are true about Ireland：