If the distance to a star doubles, by what factor does its brightness decrease?

The apparent magnitude scale is logarithmic. A difference of 5 magnitudes corresponds to a brightness difference of what factor?

What is the approximate surface temperature of the Sun in Kelvin?

Using Wien's displacement law, if a star's peak emission wavelength is halved, by what factor does its temperature increase?

The luminosity of a star is proportional to its radius squared and its temperature to the fourth power. If a star doubles in radius and doubles in temperature, by what factor does its luminosity increase?

What is the unit of Luminosity?

The spectral class of a star is primarily determined by its:

A star with a parallax angle of 0.1 arcseconds is at what distance in parsecs?

If the sun's core suddenly stopped fusion, how long would it take for the change to be observed on the surface?

Which of the following is NOT a layer of the Sun's atmosphere?