(a) make such orders as may be necessary or reasonable in all matters relating to the delivery and answering of interrogatories, the admission of documents and facts, and the discovery, inspection, production, impounding and return of documents or other material objects producible as evidence;
(b) issue summonses to persons whose attendance is required either to give evidence or to produce documents or such other objects as aforesaid;
(c) order any fact to be proved by affidavit.