ELEMENTAL ABUNDANCES OF FIELD HORIZONTAL-BRANCH STARS .4. HD 74721, 86986 AND 93329

Studies of 200-Angstrom-long regions recently obtained with a 3000-pix el-long CCD at the coude feed telescope of the Kitt Peak National Obse rvatory (KPNO) are used to extend fine analyses of the field horizonta l branch A stars HD 74721, 86986 and 93329. Spectra of other stars obt ained both at KPNO and at the Dominion Astrophysical Observatory show that previously found wavelength-dependent equivalent width systematic s are probably due to how the spectra were measured as well as to reso lution differences. The derived He/H ratios agree with the Buzzoni et al. value of 0.075, within measurement errors. Some derived elemental abundances are found to be correlated with one another.