Technology transfer comes only from nations importing new capital goods in the current account

Most trading nations do not completely specialize. Incomplete specialization is mainly due to:

a. decreasing opportunity costs. b. increasing opportunity costs. c. constant opportunity costs. d. perfectly substitutable resources.

Imagine you regressed earnings of individuals on a constant, a binary variable ("Male") which takes on the value 1 for males and is 0 otherwise, and another binary variable ("Female") which takes on the value 1 for females and is 0 oth

Because females typically earn less than males, you would expect A) the coefficient for Male to have a positive sign, and for Female a negative sign. B) both coefficients to be the same distance from the constant, one above and the other below. C) none of the OLS estimators to exist because there is perfect multicollinearity. D) this to yield a difference in means statistic.