The Extragalactic Distance Scale Key Project III. Teh discovery of Cephids and a New Distance to M101 Using the Hubble Space TelescopeWe report on the discovery of 29 cephid variables in the galaxy M101 after using the original Wide Field Camera (WFC 1) and the new Wide Field and Planetary Camera (WFPC 2) on the Hubble Space Telescope (HST), to observe a field in M101 at 14 independent epochs in F555W.