Contracts for any of the following purposes, whether contained in the bylaws or separately written, are valid when made between a cooperative and a member in which the member agrees to (1) sell, market or deliver to or through the cooperative or facilities furnished by it all or a specified part of products produced by the member or under the control of the member;
(2) authorize the cooperative or facilities furnished by it to act for the member in any manner with respect to all or a specified part of products produced by the member or under the control of the member;
(3) buy or procure from or through the cooperative or facilities furnished by it all or a specified part of goods or services to be bought or produced by the member;
(4) authorize the cooperative or facilities furnished by it to act for the member in any manner in the procurement of goods or the procurement of performance of services.