Indianapolis Mayor Joe Hogsett and Fishers Mayor Scott Fadness will this afternoon outline central Indiana efforts to land a second U.S. headquarters for Amazon.com Inc. The online retail giant last week announced plans for the $5 billion investment, which would result in up to 50,000 new jobs with an average salary topping $100,000 per year. Hogsett and Fadness say they hope to build on Amazon’s existing presence in Indiana, which includes 9,000 employees in five facilities.