Write the formula for potential energy (blank 1). Calculate the potential energy in Joules (J) of an object weighing 4 kilograms and sitting 4 meters off the ground if gravity is 9.8 meters per second squared. Enter your answer (blank 2).

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

Give the set of reactants (including an alkyl halide and a nucleophile) that could be used to synthesize the following ether: draw the molecules on the canvas by choosing buttons from the tools (for bonds and charges), atoms, and templates toolbars, including charges where needed. ch3ch2och2ch2chch3 | ch3

An atom of which element reacts with an atom of hydrogen to form a bond with the greatest degree of polarity ?