Massive star formation in Wolf-Rayet galaxies. V: Star formation rates,
  masses and the importance of galaxy interactions
  (Abridged) We have performed a comprehensive analysis of a sample of 20
starburst galaxies, most of them classified as Wolf-Rayet galaxies. In this
paper, the last of the series, we analyze the global properties of our galaxy
sample using multiwavelength data (X-ray, FUV, optical, NIR, FIR, and radio).
The agreement between our Ha-based SFR and those provided by indicators at
other wavelengths is remarkable, but we consider that the new Ha-based
calibration provided by Calzetti et al. (2007) should be preferred over older
calibrations. The FUV-based SFR provides a powerful tool to analyze the
star-formation activity in both global and local scales independently to the Ha
emission. We provide empirical relationships between the ionized gas mass,
neutral gas mass, dust mass, stellar mass, and dynamical mass with the
B-luminosity. Although all mass estimations increase with increasing
luminosity, we find important deviations to the general trend in some objects,
that seem to be consequence of their particular evolutionary histories. We
investigate the mass-metallicity relations and conclude that both the nature
and the star-formation history are needed to understand the relationships
between both properties. The majority of the galaxies follow a
Schmidt-Kennicutt scaling law of star-formation that agrees with that reported
in individual star-forming regions within M~51 but not with that found in
normal spiral galaxies. We found a relation between the reddening coefficient
and the warm dust mass indicating that the extinction is mainly internal to the
galaxies. Considering all data, we found that 17 up to 20 galaxies are clearly
interacting or merging with low-luminosity dwarf objects or HI clouds. We
conclude that interactions do play a fundamental role in the triggering
mechanism of the strong star-formation activity observed in dwarf starburst
galaxies.
