Which of the following statements is true?
1.since the sun uses its own hydrogen to create energy, it will eventually run out of fuel and burn out.
2.objects in the universe are moving toward earth, which supports the theory that the universe is shrinking.
3.the absolute magnitude of a star measure both luminosity and the stars distance from earth.
4. all the inner planets are less than one au from the sun.

Describe different biomes. what are some adaptations that organisms (plants or animals) must have to live in each biome?

Which is not true about oxygen-17 and oxygen-18?

Awater slide of length l has a vertical drop of h. abby's mass is m. an average friction force of magnitude f opposes her motion. she starts down the slide at initial speed vi. use work-energy ideas to develop an expression for her speed at the bottom of the slide. then evaluate your result using unit analysis and limiting case analysis. express your answer in terms of the variables h, m, l, vi, f and appropriate constants. vf v f