For the white dwarf supernova, the luminosity 175 days after it reaches peak brightness is about of the luminosity at peak brightness.

Assume that a person skiing high in the mountains at an altitude of h = 15100 ft takes in the same volume of air with each breath as she does while walking at sea level. determine the ratio of the mass of oxygen inhaled for each breath at this high altitude compared to that at sea level. assume that the air composition (i.e. % of air that is oxygen) is the same at sea level as it is at 15100 ft.

What effects result when there is an impact between earth and an asteroid? check all that apply. a.massive flooding. b.extinction of many life forms.c.major earthquakes change in average global temperature.d. giant dust cloud

Astep up transformer has 250 turns on its primary and 500 turns on it secondary. when the primary is connected to a 200 v and the secondary is connected to a floodlight that draws 5a, what is the power output? show all of your work.