The farming and grazing practices of the early settlers led to a natural disaster. Which of the following practices led to the creation of this ecosystem disaster? 1. Overplanting crops that could not stand drought
2. Plowing the soils so that plant materials were buried
3. Overgrazing the prairie
4. All of the above

In a particular chemical reaction, the energy of the reactants is 30 kj and the energy of the products is 5 kj. 
 the maximum energy of the system is 40 kj. sketch a potential energy diagram for this reaction. make sure to label the energy of the reactants, the energy of the products, the activation energy, and the enthalpy change for the reaction.