How many grams of oxygen were used if 3.0 moles of aluminum oxide are produced

Which supports the idea that birds and butterflies both have wings but they do not have a common ancestor with wings? a. the wings are analogous structures that evolved differently and do not have a similar internal structure. b. the wings are homologous structures that evolved differently and do not have a similar internal structure. c. wings of birds are vestigial structures, but the wing structures of bats are not vestigial. d. wings of bats are vestigial structures, but the wing structures of birds are not vestigial

What is the independent variable in this investigation? mass volume sample number substance density

What is the empirical formula for c4h8o2