For centuries, scientists believed that light waves traveled through a substance called "Ether." Which of the following facts refutes this belief? A. Light waves can propagate through a vacuum.
B. Ether has never been observed.
C. Light waves can have many different wavelengths and frequencies.
D. Light waves can travel extremely long distances.

If you go to a nutrition store and buy a supplement, you can count on the fact that it is pure and safe because supplements are regulated, controlled, and inspected by the fda.

Bob camina 200 m sur, luego trota 400 m suroeste, luego camina 200 m en una dirección 30? norte del este. a. dibuje una gráfica de los movimientos de bob. use una regla y transportador. b. use método gráfico y analíitico para hallar el desplazamiento total que bob recorrió. (magnitud y dirección) c. compare los resultados obtenidos por el método gráfico y analítico. (por ciento de diferencia).

Part a constants huck finn walks at a speed of 0.60 m/s across his raft (that is, he walks perpendicular to the raft's motion what is huck's velocity (speed and direction) relative to the river bank? express your answer to three significant figures and include the appropriate units. relative to the shore)