Which of the following is a balanced chemical equation?

SO2 + O2 + 2 H2O → 4 H2SO4

H2O2 → H2O + O2

2 Fe2O3 + 3 C → 4 Fe + 3 CO2

2 Mg + HC1 → MgCl2 + H2

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 i fracture in the crust called when land move up, down or sideways

1. explain hydrogen peroxide, h 2 o 2 properties and decomposition reaction. 2. describe how each of the following natural cycles plays a part in earth’s climate system. (a) the water cycle (b) the carbon cycle