The City of Manila enacted Ordinance No. 55-66 which imposes a municipal occupation tax on persons practicing various professions in the city. Among those subjected to the occupation tax were lawyers. Atty. Mariano Batas, who has a law office in Manila, pays the ordinance-imposed occupation tax under protest. He goes to court to assail the validity of the ordinance for being discriminatory. Decide with reasons. (2009 BAR)