A researcher who selects a sample of people of varying ages and studies them at one point in time is, by definition, using the ______ method

Daphne was sitting talking with some friends when she suddenly left the room to check on her baby. She was sure she had heard little Sandra cry out, but when she checked, Sandra was sleeping peacefully. Based on signal detection theory, the fact that Daphne thought she detected her baby's cry would be considered:

a. a hit b. a miss c. a correct rejection d. a false alarm

Most psychologists would agree that the most widely used intelligence tests:

a. have good predictive validity for academic performance b. are valid for differentiating fluid and crystallized intelligence c. have high validity for predicting creativity d. are not valid because they are seriously racially biased