CAPE CANAVERAL, Fla. (Reuters) – SpaceX’s final version of the Falcon 9 rocket, which Elon Musk aims to launch before the end of the year, will fix a potential problem with cracks in its turbopumps, the company said on Thursday. Its statement followed a report that the U.S. Government Accountability Office will flag turbine wheel cracks in the rocket’s turbopumps as a safety issue. NASA, the U.S. space agency, and the Air Force are among SpaceX’s customers.