What do ultrasounds use?

radio waves
ultraviolet waves
light waves
sound waves

The variables for this experiment include mass, volume and the materials in the various balls, as well as their densities. in part iii, you will be investigating the questionable baseball. use the drop-down menus to complete the sentences and identify the independent and dependent variables. in part iii, the independent variable, the one that is intentionally manipulated, is . in part iii, the dependent variable, the one that you measure the response in, is

Explain what it means to view something from a frame of reference. provide an example that illustrates your explanation. (4 points)

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.