A pattern of bright lines on a dark background is referred to as ...

[jace]

A pattern of bright lines on a dark background is referred to as
 
  A) an emission line spectrum
  B) an absorption line spectrum
  C) a continuous spectrum
  D) a bright spectrum

Question 2

The SI unit of time, the second, is currently defined by
 
  A) the motion of the Earth in orbit.
  B) the rotation period of the Earth.
  C) a duration of an atomic clock.
  D) a standard clock at the International Bureau of Weights and Measures in France.
  E) the time required for light to travel 1/299,792,458 of a meter.

[pikon]

Answer to Question 1

A

Answer to Question 2

C