Which animal group actually saw a drop in the number of endangered and threatened species between 1995 and 2005? a Fish
b. Reptiles
c. Birds
d. Mammals

Which best describes the activation energy of a chemical reaction? a. the combined energy of all the reactants b. the amount of energy required for a reaction to occur c. the difference in energy between products and reactants d. the potential energy stored in the bonds of reactants and products