Question

1. what does

edshift\ tell scientists about the universe?
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a. the universe is shrinking.
b. the universe is expanding.
c. stars are getting colder.
d. new planets are forming.

1. which of these is a primary piece of evidence supporting the big bang theory?

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a. the existence of black holes
b. cosmic microwave background radiation
c. the presence of oxygen in earths atmosphere
d. the phases of the moon

1. how do scientists determine the composition of distant stars?

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a. by sending probes to collect samples
b. by analyzing the light spectra (spectroscopy)
c. by measuring the stars distance from earth
d. by observing the stars color with the naked eye

1. what force is primarily responsible for maintaining the structure of the solar

Explanation:

1. Redshift refers to the stretching of light from distant objects toward longer (redder) wavelengths, which occurs when the object is moving away from the observer. This universal redshift of distant galaxies shows the universe is expanding.
2. The Big Bang Theory predicts the universe was once extremely hot, and the leftover heat from this event is cosmic microwave background radiation, which is a key, direct piece of evidence for the theory.
3. Each element produces a unique pattern of spectral lines (bright or dark) in light. By analyzing the light spectra of distant stars via spectroscopy, scientists can match these patterns to known elements to determine the star's composition.

Answer:

1. B. The universe is expanding.
2. B. Cosmic microwave background radiation
3. B. By analyzing the light spectra (spectroscopy)