Can anyone tell me what is better AP classes or dual credit?

According to the article, what are some of the drawbacks of traditional intelligence tests, and what is being done to rectify these issues?

Generate a research topic/hypothesis, for example some type of old's wives tale or cliche. identify the population of interest. how will you will randomly select in order to get a representative sample? how you will randomly assign the sample into the experimental and control group? what variable(s) will each group receive? identify the independent and dependent variables. explain how you will control for outside/confounding variables. the following is an example: example: topic: does more time spent studying lead to better grades on exams in college students. population of interest: all students enrolled at college random selection: access database with the names of all students and every 5th student will be involved in study. random assignment: every other student gets sent to the experimental group. experimental group: studies for two hours per night 5 days a week. control group: studies for less than 2 hours per night 5 days a week. independent variable: time spent studying dependent variable: exam scores control for: all students study on same nights, have same instructor, take same posttest, study same material, take exam at same time, etc. everything should be the same between the two groups except the amount of time spent !

Why did the separate car act not violate the 14th amendment?