What is a confounding variable?
a. a confounding variable is a response variable that was not considered in a study whose effect cannot be distinguished from a second explanatory variable in the study.
b. a confounding variable is an explanatory variable that was considered in a study whose effect cannot be distinguished from a second explanatory variable in the study.
c. a confounding variable is a response variable that has an effect on the explanatory variable, but it cannot be accurately measured in the study.
d. a confounding variable is the explanatory variable on which a study has been focused.

Suppose that the u.s. dollars-mexican pesos exchange rate is fixed by the u.s. and mexican governments. assume also that labor is mobile between the united states and mexico due to low transportation costs.which of the following situations is likely to happen as a result of a simultaneous increase in the demand for u.s. goods and decrease in the demand for mexican goods? (pick mexican unemployment rate increases, and the country undergoes bad economic times for a sustained u.s. unemployment rate increases, and the country undergoes bad economic times for a sustained mexican unemployment rate rises at first, but it soon drops as unemployed mexicans move to the united states for mexican unemployment rate rises at first, but then it drops as mexican pesos depreciate against u.s. dollars.