Which one will produce a change in momentum? a) A car is driving down the road and the driver applies the brakes b) A quarterback dodges a tackle from the defense by changing his direction as he runs (a "juke") c) As you approach the finish line, you start running harder and speeding up d) A rocket is launching into space and losing rocket fuel as it shoots upwards d) All of the above

Engineers find a new metal that is stronger than steel but much lighter. this material is also significantly cheaper than what is currently used for most aircraft, available in large quantities, and easy to manufacture. the engineers are excited because this new material will lower the costs of buying and operating airplanes for companies. what is probably the best step for the engineers to make next?