To facilitate effective and harmonious planning of the metropolitan area, the Boards and the Councils concerned and other county, municipal and local governmental agencies concerned shall submit to the Metropolitan Planning Commission all proposals for plans and amendments or revisions thereto, as well as other proposals, recommendations and reports on matters with which the planning commission is concerned. In the pursuance of its duties, the Metropolitan Planning Commission may seek the advice, cooperation and collaboration of appropriate federal, state, municipal and other local governmental offices, departments, agencies, and instrumentalities, educational institutions and research organizations, whether public or private, and of civic groups and private persons and organizations. The Planning Commission also shall cooperate and confer with, and upon request supply information to, federal, state, municipal and other local governmental agencies, and so far as possible cooperate with planning agencies of adjoining areas, on matters of mutual interest relevant to its activities. Whenever such cooperation or assistance includes the rendering of technical services, such services may be rendered free or in accordance with an agreement for reimbursement. The Planning Commission also shall advise and supply information, as far as possible, to civic groups and private persons and organizations who may request such information and advice, and who study or otherwise concern themselves with the metropolitan area's problems and development, insofar as such problems and development may be relevant to the activities of the planning commission.