WASHINGTON, Aug. 9 -- NASA issued the following news release: * * * NASA Selects Contractors to Supply Centers with Helium NASA has chosen a group of contractors to supply multiple agency facilities with liquid and gaseous helium for at least the next two years. The NASA Agency-wide Supply of Liquid and Gaseous Helium contract is a fixed-price indefinite-delivery requirements contract with firm-fixed-price delivery orders. The awards have a total estimated value of approximately $105.1 milli more PR