A ball rolls from x=10m to x=-25m in 2.5 seconds. What was it’s average velocity?

What is work? how much work is done to move an object 0 meters?

What is a neurotransmitter involved in mood reward, addiction, and motor behaviors?

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?