Why was pearl harbor attack such a shock to the united states

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

Alarge increase in gas prices creates a demand for cars with good gas milage. it takes months for car companies to make these cars. how do you describe this market for cars

Name two things the mycenaeans learned from the minoans