CEDAR RAPIDS — One-way Second Avenue from Sixth Street SW across the bridge to First Street SE will open as a two-way street on Friday, weather permitting, the city said.Next week, similar work will take place on Third Avenue, which is changing from one-way to two-way from Sixth Street SW to Third Street SE.The conversions of the two arterial streets into and out of downtown have been discussed by the City Council for the last several years.