2 preliminary DCAT questions

Sorry for the duplicate post; but it appears my original message was not
sent as plain text, making it difficult to read, so I'm trying another mail
account.

As stated in my previous post I'm new to DCAT and coming up to speed.
Wonder if I could solicit  your advice on a couple of use cases:

1) Compressed download files contain common data types, such as CSV, Excel
or ESRI shapefiles. Ostensibly, the format property should match the media
type, but is there a good way to indicate the archive contents?  For
example:

:dataset
  a dcat:Download ;
  dcat:accessURL <
http://databank.worldbank.org/databank/download/WDIandGDF_excel.zip> ;

  dcat:format [
    a dc:IMT ;
    rdf:value "application/zip" ;
    rdfs:label "Compressed Excel" ;
  ];
.

:dataset
  a dcat:Download ;
  dcat:accessURL <
http://haitidata.org/hti_geology_hydrogeology_bme_polygon_2010.zip> ;

  dcat:format [
    a dc:IMT ;
    rdf:value "application/zip" ;
    rdfs:label "ESRI Shapefile" ;
  ];
.

2) Any suggestions for including the contact information for a dataset,
i.e., who to call with questions? dc:publisher, dc:creator and dc:mediator
are close, but not quite.

Thanks,
Tim Herzog
World Bank