According to ohm's law if you don't change the value of the resistor & you double the voltage in a circuit the amount of current flowing will a. be multiplied by the amount of resistance b. double c. remain the same also d. divide it in half

Students design a model roller-coaster track. they place a rubber ball at the highest point on the track and let it go. the ball rolls along the track pulled only by the force of gravity. eventually, it comes to a stop. which change to the design will result in the ball moving the greatest distance?