By Stephen Eisenhammer, Senior Contributing Reporter
RIO DE JANEIRO, BRAZIL - Having replaced two executives at the end of April, there are rumors of more to come, as Petrobras´ CEO, Maria das Gracas Foster, begins to oversee changes at the top of Brazil’s state-run energy giant after taking control in February. Refining chief, Paulo Roberto Costa, and Renato Souza Duque, Petrobras' engineering chief, were replaced by Jose Carlos Cosenza and Richard Olm on April 27th.
Then, last Thursday, May 3rd . . .