  We have demonstrated the resonant control of the elastic scattering cross
sections in the vicinity of Feshbach resonances between $^{23}$Na$^{40}$K
molecules and $^{40}$K atoms by studying the thermalization between them. The
elastic scattering cross sections vary by more than two orders of magnitude
close to the resonance, and can be well described by an asymmetric Fano
profile. The parameters that characterize the magnetically tunable s-wave
scattering length are determined from the elastic scattering cross sections.
The observation of resonantly controlled elastic scattering cross sections
opens up the possibility to study strongly interacting atom-molecule mixtures
and improve our understanding of the complex atom-molecule Feshbach resonances.
