Which of the following is true about the speed of light? A) It depends on the wavelength
B) In a vacuum, it is a constant value that does not depend on the observer.
C) It is slowest in a vacuum unless an observer is moving towards the source.
D) In a vacuum, it varies depending on the color of the light.

Explain the difference between a physical change and chemical change

Like ancient india, ancient china was generally ruled by a dynasty. which of these statements best describes this system of rule? a. rule of the country was passed down by inheritance. o b. rule of the country was voted on by the people. o c. rule of the country was decided by a committee of elders. o d. rule of the country changed hands through violent uprisings. submit

Discuss the ways in which the northern and southern economies and social customs differed in the decade prior to the civil war. why are they characterized as having “two distinct societies”?