  The first measurements of antineutrino charged-current quasielastic ($\numub$
CCQE, $\numu + N \to \mup + N'$) and neutral-current elastic ($\numub$ NCE,
$\numu + N \to \numu + N$) cross sections with $< E_{\bar{\nu}} >$ $<$ 1 GeV
are presented. To maximize the precision of these measurements, many
data-driven background measurements were executed, including a first
demonstration of charge separation using a non-magnetized detector. Apart from
extending our knowledge of antineutrino interactions by probing a new energy
range, these measurements constrain signal and background processes for current
and future neutrino oscillation experiments and also carry implications for
intra-nuclear interactions.
