Cells are made mostly of what compound?

Are the earth's ocean floor and continents the same age geologically? why or why not?

Which statement correctly describes other ways in which nebulae and stars are different? a. a star always has a higher density than a nebula. b. stars can form inside a nebula but a nebula can never be produced by any star. c. stars can never form inside a nebula but a nebula can be produced by any star. d. a nebula always has a higher density than a star. reset submit

Consider the venn diagram of plant reproduction. where in this image, areas a - d, would you insert the picture of the orange lily?