Every licensee shall carry his license certificate on his person at all times when engaged in the activity for which the license was granted, except that where such activity is conducted at a fixed place or establishment, the license certificate shall be exhibited at all times in some conspicuous place in his place of business. The licensee shall exhibit the license certificate when applying for a renewal and on demand of any police officer or person representing its issuing authority.
('75 Code, § 14-10) Penalty, see § 110.99