Prepare a dialogue between 2 friends about the”Prospects of development in our country Plz help me

In which research method does a researcher change the value of one variable to determine how the change affects another variable? a. experiment b. observational research c. survey d. case study

Donald is studying the eating habits of all students attending his school. he samples the population by dividing the students into groups by grade level and randomly selecting a proportionate number of students from each group. he then collects data from the sample. which type of sampling is used? select the correct answer below: systematic sampling convenience sampling stratified sampling cluster sampling

Which phrase correctly completes the statement? "the korean war " lasted 3 years. has never ended. was won by north korea. was won by south korea lasted 3 years. has never ended. was won by north korea. was won by south korea.