How to use hyrogen proxide for surgery wounds

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

Which of the following elements would you expect to have the lowest ionization energy value? fluorine, lithium, neon, nitrogen

Acontrol during an experiment. might change remains constant does not exist does change