These are all true except <span>"D. Natural selection usually causes a species to change suddenly," which is false. Natural selection and the subsequent changes to a species takes many thousands of years to have observable results. </span>
The answer is the equilibrium concentrations or pressures of each species that occurs in the equilibrium expression, or enough information to determine them. These values are substitued into the equilibrium expression and the value of the equilibrium constant is then calculated.
It should be recorded in miligrams
