  We report observations of two nearby Type Ia supernovae (SNe Ia) for which
observations of Cepheid variables in the host galaxies have been obtained with
the Hubble Space Telescope: SN 1994ae in NGC 3370 and SN 1998aq in NGC 3982.
For NCG 3370, we used the Advanced Camera for Surveys to observe 64 Cepheids
that yield a distance of 29 Mpc, the farthest direct measurement of Cepheids.
We have measured emission lines from H II regions in both host galaxies which
provide metallicity-dependent corrections to their period-luminosity relations.
These two SNe Ia double the sample of ``ideal'' luminosity calibrators: objects
with well-observed and well-calibrated light curves of typical shape and with
low reddening. By comparing them to all similarly well-measured SNe Ia in the
Hubble flow, we find that H_0 = 73 +/- 4 (statistical) +/- 5 (systematic). A
detailed analysis demonstrates that most of the past disagreement over the
value of H_0 as determined from SNe Ia is abated by the replacement of past,
problematic data by more accurate and precise, modern data.
