A researcher records scores on a parenting skills assessment among parents who are married and parents who are single before and again after a family training course. He compares parenting skills scores at both times for both types of parents. What type of quasi-experimental research design is described in this example?

Which of the following situations best demonstrates the principle of separation of powers in the u.s. government? a. the president can veto laws passed by the legislature. b. the courts must approve constitutional amendments. c. states create their own educational policies. d. members of the legislature are elected by voters.