Only those persons found qualified in the public examinations held by the Central Government or adjudged qualified by the Ministry of Public Service Registration may be a candidate for the office of Mayor. ARTICLE 114. The Mayor shall administer the affairs of the municipality in accordance with the principles of municipal self-government and, under direction of the competent supervising authority, execute matters assigned by the Central or Provincial Government. ARTICLE 115. The organization of the Municipal Council and Municipal Government as well as the election and recall of the Members of the Municipal Council and the Mayor shall be determined by law. CHAPTER VI. NATIONAL ECONOMIC LIFE ARTICLE 116. The economic system of the Republic of China shall be based upon the Min Shêng Chu I (Principle of Livelihood) and shall aim at national economic sufficiency and equality. ARTICLE 117. The land within the territorial limits of the Republic of China belongs to the people as a whole. Any part thereof the ownership of which has been lawfully acquired by an individual or individuals shall be protected by, and subject to, the restrictions of law. The State may, in accordance with law, tax or expropriate private land on the basis of the value declared by the owner or assessed by the Government. Every landowner is amenable to the duty of utilizing his land to the fullest extent. ARTICLE 118. All subterranean minerals and natural forces which are economically utilizable for public benefit, belong to the State and shall not be affected by private ownership of the land. ARTICLE 119. The unearned increment shall be taxed by means of a land-value-increment tax and devoted to public benefit. ARTICLE 120. In readjusting the distribution of land, the State shall be guided by the principle of aiding and protecting the land-owning farmers and the land-utilizing owners. ARTICLE 121. The State may, in accordance with law, regulate private wealth and enterprises when such wealth and enterprises are considered detrimental to the balanced development of national economic life. ARTICLE 122. The State shall encourage, guide and protect the citizens' productive enterprises and the nation's foreign trade. ARTICLE 123. All public utilities and enterprises of a monopolistic nature shall be operated by the State; except in case of necessity when the State may specially permit private operation. The private enterprises mentioned in the preceding paragraph may, in case of emergency for national defense, be temporarily managed by the State. The State may also, in accordance with law, take them over for permanent operation upon payment of due compensation. ARTICLE 124. In order to improve the workers' living conditions, increase their productive ability and relieve unemployment, the State shall enforce labor protective policies. Women and children shall be afforded special protection in accordance with their age and physical condition.