Question: Perform the operations of conversion, obversion, and contraposition as indicated.
Convert the following propositions and state whether the converse is logically equivalent or not logically equivalent to the given proposition.
a. All hurricanes are storms intensified by global warming.
b. No sex-change operations are completely successful procedures.
c. Some murals by Diego Rivera are works that celebrate the revolutionary spirit.
d. Some forms of carbon are not substances with a crystalline structure.