Along a straightline production possibilities curve: O the opportunity cost of production of a good is zero. 0 the opportunity cost of production of a good falls as its output increases. O the opportunity cost of production of a good rises as its output increases. 0 the opportunity cost of production of a good is constant. Economists need to develop abstractions in order to: O avoid analyzing real-world economic interactions, which are too complicated to understand. O distinguish normative economic behavior from positive economic behavior. 0 avoid committing the fallacy of composition. O understand and explain economic behavior. Suppose Carrie's utility function for clams is as follows: If she consumes 1 clam, she gets 10 units of total utility; for 2 clams, she gets 18 units of total utility; for 3 clams, she gets 24 units of total utility; for 4 clams, she gets 28 units of total utility; for 5 clams, she gets 30 units of total utility; and for 6 clams, she gets 26 units of total utility. 0 Carrie gets 9 units of marginal utility for the 2nd clam. 0 Carrie gets 8 units of marginal utility for the 3rd clam. 0 Carrie gets Y units of marginal utility for the 4th clam. 0 None of the above are true