Which of the following required freedmen to know certain sections of the constitution in order to vote

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

Nami conducts an investigation on plants. she places a grow light on a timer to give the plants different amounts of light to see if this would affect their growth. in this investigation, the amount of light is the .

Which of the following best summarizes the idea represented by this graph?