4. IV: Distance ball goes, DV: Type of bat, C: Type of ball, and the length of the experiment (6 weeks).
Hypothesis: If the player uses the aluminum bat, then it will have a greater distance then the balls hit with the wooden bat.
5. IV: Light produced, DV: Light Bulb wattage. C: The lamp
Hypothesis: If the bulb has more energy yen it will produce more light.
IV is what you don't control/the outcome of the experiment, and DV is the part of the experiment that you have control over. The constant remains the same throughout the experiment.