As important as it is to plan ahead, sometimes you

If a substance is in the gas phase, which of qualities of the gas will stay constant? a: volume b: mass c: shape d: position of particles

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?

Would it be correct to say the doppler effect is the apparent change in the speed of a wave due to the motion of the source? be sure to fully explain your position using at least 3 complete content related sentences.