The monies in said revolving fund may be expended for the following purposes:
(a) For the purchase of livestock to replace livestock sold or used in connection with said institution and the keeping up and maintaining its dairy herd;
(b) for the purchase of material, appliances and equipment used in such business enterprises, occupations, factories, or shops, and other business carried on at such institution;
(c) for the purchase of feed for the livestock owned by said institution;
(d) for the purchase of materials and parts necessary in repairing and maintaining the machinery and equipment for the industries of said institution, and for the payment of labor incidental thereto.
Laws 1941, p. 267, § 4.