 Complete the following phrase:  At the 2012 London Olympics, Richards-Ross finished the womens 400-meter sprint in 49.55 seconds to finally win the gold medal that eluded her four years ago. In the Olympic 200 meter final, Richards-Ross finished fifth in 22.39 seconds, while American compatriots Allyson Felix and Carmelita Jeter won gold and bronze, respectively. She concluded the 2012 Summer Olympics by running 49.1 seconds on the anchor leg of the gold medal-winning U.S. womens 