Studying a spectrum from a star can tell us a lot. All of the ...

[HudsonKB16]

Studying a spectrum from a star can tell us a lot. All of the following statements are true except one. Which statement is not true?
 
  A) The total amount of light in the spectrum tells us the star's radius.
  B) The peak of the star's thermal emission tells us its temperature: hotter stars peak at shorter (bluer) wavelengths.
  C) We can identify chemical elements present in the star by recognizing patterns of spectral lines that correspond to particular chemicals.
  D) Shifts in the wavelengths of spectral lines compared to the wavelengths of those same lines measured in a laboratory on Earth can tell us the star's speed toward or away from us.

Question 2

According to the nebular theory, as an interstellar cloud forms a new star and planetary system it
 
  A) expands, cools down, and spins slower
  B) contracts, heats up, and spins faster
  C) expands, cools down, and spins faster
  D) contracts, heats up, and spins slower

[tofugiraffe]

Answer to Question 1

A

Answer to Question 2

B

[HudsonKB16]

TYSM

[cdmart10]

Gracias!