20. Each regular exhibitor may receive an award, although his exhibit be joined with that of others in a single installation. Only one award shall be given to a collective exhibit, but the names of all the contributors to such collective exhibit may be entered on the diplomas awarded, and each participant shall receive a copy. If so desired by a group of exhibitors, a single award may be made to an individual representing such group. 21. An exhibit shall receive only one award in any group. The same object, shown in several groups and adjudged by more than one jury, shall be entitled only to the highest award accorded to it. An exhibitor who has different objects entered as exhibits in different groups may be given an award in each group. 22. Exhibitors who desire to have their exhibits excluded from competition shall notify the chief of department as to their wishes when making application for space, giving their reasons at length for their request and objections to a competitive exhibit; and these papers shall be transmitted through the directory of exhibits to the president of the Louisiana Purchase Exposition Company with such recommendations as may be deemed necessary. Exhibits thus exempted from competition shall not be examined by the juries, and shall not be entitled to official recognition in connection with the system of awards. 23. In addition to the awards prescribed for exhibitors, an award may also be made to the inventor, designer, or artisan, who, as collaborator, has, in the judgment of the jury, shown more than ordinary skill in connection with an exhibit. A collaborator is a person who has distinguished himself as the designer or producer of remarkable objects shown at the exposition. He is not a person who has merely aided in the arrangement or installation of exhibits. In order that this may be equitably accomplished, each exhibitor who has received an award may furnish the chief of his respective department, for transmission to the proper jury, a list of the names of his collaborators, arranged in order of merit, based on skill, ability, magnitude and value of work, and length of service. It will then remain for the jury of awards to determine whether the assistance rendered by the persons named in the manner described has been sufficient to entitle them, or any of them, to the rank of collaborator, and to name the award which may be conferred therefor. 24. Whenever it is applicable, a decimal scale system shall be used in judging the merits of exhibits, 100 representing perfection; and as a suggestion to juries, for instance, in commercial exhibits, the following is offered: